See the explanation part for the complete Solution.
Explanation:
Configure Dynamic Data Masking on the email column in:
SalesLT.Customer
The column is normally:
EmailAddress
Use the built-in masking function:
email()
Microsoft documents that Dynamic Data Masking hides sensitive data in query results for nonprivileged users without changing the stored data. The built-in email() masking function exposes the first letter and returns the masked format [email protected], which exactly matches the requirement.
Method 1 - SSMS / T-SQL Method
This is the fastest and most reliable method.
Step 1: Connect to db1
Open SQL Server Management Studio.
Connect to the Azure SQL logical server that hosts db1.
Open a query window against database:
db1
Step 2: Apply the email mask
Run:
ALTER TABLE [SalesLT].[Customer]
ALTER COLUMN [EmailAddress]
ADD MASKED WITH (FUNCTION = ' email() ' );
This adds a Dynamic Data Masking rule to the EmailAddress column. The actual email address remains stored in the table, but users without permission to view unmasked data will see the masked value. Microsoft' s documented syntax for adding an email mask is ALTER COLUMN Email ADD MASKED WITH (FUNCTION = ' email() ' ).
Step 3: Verify that the column is masked
Run:
SELECT
OBJECT_SCHEMA_NAME(mc.object_id) AS schema_name,
OBJECT_NAME(mc.object_id) AS table_name,
c.name AS column_name,
mc.masking_function
FROM sys.masked_columns AS mc
JOIN sys.columns AS c
ON mc.object_id = c.object_id
AND mc.column_id = c.column_id
WHERE OBJECT_SCHEMA_NAME(mc.object_id) = ' SalesLT '
AND OBJECT_NAME(mc.object_id) = ' Customer '
AND c.name = ' EmailAddress ' ;
Expected result:
schema_name SalesLT
table_name Customer
column_name EmailAddress
masking_function email()
Step 4: Test as a non-administrative user
If you have a test user, run:
EXECUTE AS USER = ' TestUser ' ;
SELECT TOP (10)
EmailAddress
FROM SalesLT.Customer;
REVERT;
Expected output should look like:
[email protected]
[email protected]
[email protected]
A user with administrative privileges, db_owner, or UNMASK permission can still see the original email value. Microsoft states that users with administrative rights such as server admin, Microsoft Entra admin, and db_owner can view the original unmasked data.
Method 2 - Azure Portal Method
Use this if the simulation expects portal configuration.
Step 1: Open db1
Sign in to the Azure portal.
Search for SQL databases.
Open database:
db1
Step 2: Open Dynamic Data Masking
From the db1 page:
Security > Dynamic Data Masking
Microsoft states that for Azure SQL Database, Dynamic Data Masking can be configured in the Azure portal from the SQL database configuration pane under Security > Dynamic Data Masking.
Step 3: Add a masking rule
Add a mask for the email column:
Setting
Value
Schema
SalesLT
Table
Customer
Column
EmailAddress
Masking field format
Email
Masking function
email()
Then select:
Save
The portal may show the mask type simply as:
Email
That is the correct option because it maps to the email() masking function.
Important Permission Check
Dynamic Data Masking only affects users who do not have permission to view unmasked data.
If a non-administrative user was previously granted UNMASK, remove it:
REVOKE UNMASK TO [UserName];
Or, if a role was granted UNMASK, revoke it from the role:
REVOKE UNMASK TO [RoleName];
Do not grant UNMASK to normal users. UNMASK allows users to bypass masking and see the original values. Microsoft documents that UNMASK permission controls whether users can view masked or original data.
Final Exam-Lab Action
Run this against db1:
ALTER TABLE [SalesLT].[Customer]
ALTER COLUMN [EmailAddress]
ADD MASKED WITH (FUNCTION = ' email() ' );
Then verify:
SELECT
OBJECT_SCHEMA_NAME(object_id) AS schema_name,
OBJECT_NAME(object_id) AS table_name,
name AS column_name,
masking_function
FROM sys.masked_columns
WHERE OBJECT_SCHEMA_NAME(object_id) = ' SalesLT '
AND OBJECT_NAME(object_id) = ' Customer '
AND name = ' EmailAddress ' ;
The task is complete when non-administrative users querying SalesLT.Customer.EmailAddress see masked email values such as:
[email protected]

Basic Concept: This question tests plan and implement data platform resources in the DP-300 exam context.
The correct choice is determined by the exact service boundary and operational requirement stated in the scenario.
Why B is Correct: From SQLVM1, uninstall the SQL Server instance. is an Azure data-platform feature, but it must match the workload model, service tier, migration path, or deployment constraint described in the scenario. The scenario asks for: You need to change the Microsoft SQL Server instance on SQLVM1 to the Standard edition. That makes From SQLVM1, uninstall the SQL Server instance. the option that satisfies the required Azure SQL layer and operational outcome.
Why A is Wrong: From the SQL Server Installation Center on SQLVM1. run the Edition Upgrade wizard. is an Azure data-platform feature, but it must match the workload model, service tier, migration path, or deployment constraint described in the scenario. It applies to a different Azure data-platform design than the one the question is testing.
Why C is Wrong: From the SQL Server Installation Center on SQLVM1. run the Repair wizard. is an Azure data-platform feature, but it must match the workload model, service tier, migration path, or deployment constraint described in the scenario. It mismatches the target platform, migration method, compute tier, or deployment model described in the scenario, so it would not satisfy the workload as stated.
Why D is Wrong: From the Azure portal, reconfigure SQLVM1. is an Azure data-platform feature, but it must match the workload model, service tier, migration path, or deployment constraint described in the scenario. It applies to a different Azure data-platform design than the one the question is testing.

Reference:
https://docs.microsoft.com/en-us/sql/relational-databases/performance/monitoring-performance-by-using-the- query-store?view=sql-server-ver15 Basic Concept: This question tests performance optimization for SQL workloads, including Query Store, automatic tuning, index/statistics maintenance, and engine-level resource behavior.
Why D is Correct: dynamic management views matches the expected DP-300 administration action. dynamic management views is related to operational monitoring or tuning, but it must match the exact signal needed:
query history, resource utilization, wait/blocking detail, or automatic remediation. The question is not asking for a general Azure capability; it is asking for the feature that produces this result: You need to identify which query is causing the issue and retrieve the execution plan for the query.
Why A is Wrong: the Azure portal is related to operational monitoring or tuning, but it must match the exact signal needed: query history, resource utilization, wait/blocking detail, or automatic remediation. It does not expose the required metric, query history, wait/blocking signal, or tuning mechanism; using it would not give the administrator the evidence requested.
Why B is Wrong: Extended Events is related to operational monitoring or tuning, but it must match the exact signal needed: query history, resource utilization, wait/blocking detail, or automatic remediation. It is useful in other troubleshooting paths, but this scenario requires a more specific monitoring or optimization feature.
Why C is Wrong: Query Store captures query text, plans, and runtime statistics, making it central for reviewing query history and troubleshooting plan regressions. It would produce a different operational signal than the one needed to investigate, alert, or tune the workload in this question.

To react to increased workloads and increase streaming units, consider setting an alert of 80% on the SU Utilization metric. Also, you can use watermark delay and backlogged events metrics to see if there is an impact.
Note: Backlogged Input Events: Number of input events that are backlogged. A non-zero value for this metric implies that your job isn't able to keep up with the number of incoming events. If this value is slowly increasing or consistently non-zero, you should scale out your job, by increasing the SUs.
Reference:
https://docs.microsoft.com/en-us/azure/stream-analytics/stream-analytics-monitoring

Explanation:

Basic Concept: This question tests choosing the correct Azure migration approach by matching the source platform, target service, downtime tolerance, and administrative effort.
Why the selected answer is Correct: The selected values fit this scenario because they apply the required Azure SQL configuration at the correct scope and sequence: The solution must use the highest level of security when connecting to storage1.
Why the alternate choices are Wrong: The alternate selections would either use a migration tier that does not match the downtime requirement, choose a network resource that does not support the migration path, or add an unnecessary deployment component.