A: Roll-up summary fields can cause the parent record to go through Save:
When a roll-up summary field on a parent object (like Account) is updated due to changes in child records (like Branch), the parent record (Account) is implicitly saved again.
This can result in the execution of the trigger on the parent object. Developers must consider this behavior to avoid unintended recursion or infinite loops.
Reference:Roll-Up Summary Field Considerations
C: The trigger may fire multiple times during a transaction:
Triggers can execute multiple times within a single transaction, especially when there are operations such as updates to the parent record caused by roll-up summary fields or workflows.
Developers should implement logic to ensure that the trigger handles multiple executions correctly (e.g., using a static variable to prevent recursion).
Reference:Apex Trigger Best Practices
Why not the other options?
B: Duplicate rules are executed once all DML operations commit to the database:
This is incorrect because duplicate rules executebeforethe DML operation is committed. Duplicate rules prevent duplicate records from being created or updated before the database operation occurs.
Reference:Duplicate Rules Execution
D: The validation rules will cause the trigger to fire again:
This is incorrect because validation rules do not cause triggers to fire again. Validation rules validate the record and may prevent DML operations, but they do not independently re-trigger the Apex trigger.
References:
Trigger Context and Recursion
Roll-Up Summary Field Documentation