According to the ACAMS CAMS Certification Study Guide (6th edition), a financial institution (FI) should update its ML/TF risk assessment when there are changes in its business activities, customer base, or operating environment that may affect its exposure to ML/TF risks1 Some examples of such changes are:
When new products, services or customer types are introduced: New products, services or customer types may introduce new or increased ML/TF risks that the FI may not have previously considered or addressed. For example, offering online banking, prepaid cards, or cross-border remittances may create new opportunities for money launderers or terrorist financiers to exploit the FI's systems and processes. Therefore, the FI should assess the ML/TF risks associated with the new products, services or customer types and implement appropriate controls to mitigate them12 When the institution faces a merger or acquisition: A merger or acquisition may result in the FI inheriting the ML/TF risks of the other entity, as well as the potential liabilities and reputational damage that may arise from any ML/TF issues or violations. Therefore, the FI should conduct a due diligence on the other entity's ML/TF risk assessment, policies, procedures, and controls, and identify any gaps or weaknesses that need to be addressed. The FI should also integrate and harmonize the ML/TF risk assessment and compliance programs of the merged or acquired entity with its own13 References: 1: ACAMS CAMS Certification Study Guide (6th edition), page 32. 2: Money laundering/terrorism financing risk assessment | AUSTRAC4 3: MONEY LAUNDERING & TERRORIST FINANCING (ML/TF) RISK ASSESSMENT METHODOLOGY5, page 4.
Reference: https://www.fatf-gafi.org/media/fatf/content/images/National_ML_TF_Risk_Assessment.pdf

A subpoena is a legal order that requires a person or an entity to produce documents, information, or testimony related to a legal matter. A financial intelligence unit (FIU) is a specialized unit within a financial institution that is responsible for detecting, analyzing, and reporting suspicious activities and transactions. When a bank receives a subpoena regarding one of its clients, the FIU should review the subpoena and perform a transaction review to determine if there is any evidence of money laundering, terrorist financing, fraud, or other criminal activity involving the client. The FIU should also respond fully to the subpoena by providing the requested information and documents, unless there is a valid reason to object or seek a protective order. The FIU should not adjust the client's risk score, file a SAR, or close the client's account based solely on the receipt of the subpoena, as these actions may be premature, inappropriate, or illegal. Adjusting the client's risk score may require further investigation and due diligence. Filing a SAR may be unnecessary or misleading if the subpoena does not indicate any suspicious activity. Closing the client's account may violate the bank's contractual obligations, customer service standards, or anti-discrimination laws. Moreover, these actions may alert the client or the subject of the investigation to the existence of the subpoena, which may interfere with the legal process or jeopardize the safety of the bank or its employees.
References:
Subpoena Responses for Financial Institutions
Requests by Law Enforcement for Financial Institutions to Maintain Accounts SUBPOENA COMPLIANCE UPDATE
[ACAMS Study Guide, 6th Edition, Chapter 5, p. 140]

According to the Basel guidelines on customer due diligence for banks, a trust is a legal arrangement whereby a person (the settlor or grantor) transfers the legal ownership of specific assets to another person or entity (the trustee) to hold for the benefit of a third person or persons (the beneficiaries)1. The Basel guidelines recommend that banks should identify and verify the identity of the following parties to determine the true nature of the trust relationship:
The trustee, who is the person or entity that has the legal authority and duty to manage the trust assets and distribute them to the beneficiaries according to the trust deed2. The trustee may also be the settlor, the beneficiary, or both, depending on the type and structure of the trust3.
The beneficiaries, who are the persons or entities that have a beneficial interest in the trust assets or income, either presently or in the future4. The beneficiaries may be named individuals, classes of persons, or charitable causes.
The settlor or grantor, who is the person or entity that creates the trust and transfers the legal ownership of the assets to the trustee. The settlor or grantor may also retain some rights or powers over the trust, such as the ability to appoint or remove trustees, beneficiaries, or protectors.
The other three options are incorrect because:
Respondents are not trust parties, but rather financial institutions that maintain correspondent banking relationships with other financial institutions. Respondents are not relevant for the identification of the trust relationship, but rather for the due diligence of the correspondent banking relationship.
Payees are not trust parties, but rather persons or entities that receive payments from the trust or other sources. Payees are not relevant for the identification of the trust relationship, but rather for the monitoring of the transactions and activities of the trust.
Trust administrators are not trust parties, but rather persons or entities that provide administrative services to the trust, such as accounting, record-keeping, or tax compliance. Trust administrators are not relevant for the identification of the trust relationship, but rather for the assessment of the risk and complexity of the trust.
References:
1: Basel Committee on Banking Supervision, Customer due diligence for banks, October 2001, 4, p. 17 2:
Basel Committee on Banking Supervision, Customer due diligence for banks, October 2001, 4, p. 17 3:
ACAMS, CAMS Study Guide, 6th Edition, Chapter 5, p. 111 4: Basel Committee on Banking Supervision, Customer due diligence for banks, October 2001, 4, p. 17 : ACAMS, CAMS Study Guide, 6th Edition, Chapter 5, p. 111 : Basel Committee on Banking Supervision, Customer due diligence for banks, October
2001, 4, p. 17 : ACAMS, CAMS Study Guide, 6th Edition, Chapter 5, p. 111 : Basel Committee on Banking Supervision, Customer due diligence for banks, October 2001, 4, p. 10 : ACAMS, CAMS Study Guide, 6th Edition, Chapter 5, p. 112 : ACAMS, CAMS Study Guide, 6th Edition, Chapter 5, p. 112

it describes the organization that a national Financial Intelligence Unit (FIU) should consider becoming a member of, which is the Egmont Group. The Egmont Group is an international network of FIUs that was established in 1995 to facilitate the exchange of financial intelligence and information among its members, and to promote cooperation and coordination in the fight against money laundering and terrorist financing. The Egmont Group currently has 166 member FIUs from different jurisdictions, and provides them with various benefits, such as access to secure communication channels, best practices, training, and technical assistance.
The Egmont Group also works closely with other international organizations, such as the Financial Action Task Force (FATF), the United Nations, and the World Bank, to enhance the global anti-money laundering and counter-terrorist financing (AML/CTF) framework.
The other options are not necessarily organizations that a national FIU should consider becoming a member of, although they may have some relevance or influence on the AML/CTF field. Option B describes the Wolfsberg Group, which is an association of 13 global banks that was formed in 2000 to develop standards and guidance for the financial industry on AML/CTF and other financial crime issues. The Wolfsberg Group is not an organization for FIUs, but rather for financial institutions. Option C describes the Financial Action Task Force (FATF), which is an inter-governmental body that was established in 1989 to set the international standards and recommendations for AML/CTF and to monitor the compliance and effectiveness of its members and other jurisdictions. The FATF is not an organization for FIUs, but rather for governments and policy-makers. Option D describes the Basel Committee, which is a forum of central bank governors and heads of banking supervision authorities from 28 jurisdictions that was established in 1974 to enhance the quality and consistency of banking supervision and regulation. The Basel Committee is not an organization for FIUs, but rather for banking regulators and supervisors.
References:
ACAMS CAMS Certification Video Training Course - 6th Edition1
Exam CAMS: Certified Anti-Money Laundering Specialist (the 6th edition)2 ACAMS CAMS Study Guide - 6th Edition, Chapter 5, pages 108-109
https://www.acams.org/wp-content/uploads/2019/09/ACAMS-CAMS-Study-Guide-6th-Edition-Chapter-5.pdf

A lack of information about beneficial owners is a red flag for potential money laundering or terrorist financing. It is important to identify who the actual owners of the company are to understand their potential risk exposure.
Confusing details about the proposed business activity and lack of knowledge about the proposed business are also red flags for potential money laundering or terrorist financing. This could indicate that the proposed business activity is not legitimate and is being used to conceal illegal activities.
Therefore, these two observations should be escalated to the compliance officer for further investigation.