Which statement is true regarding savepoints?

In Salesforce Apex, a Database.Savepoint allows a developer to define a point in a transaction that can be returned to if an error occurs, effectively undoing database changes. However, it is critical to understand what is—and is not—affected by a rollback. According to the platform specifications, while database records (DML operations) are reverted to their state at the time the savepoint was set, static variables are not reverted (Option B). Static variables persist across the entire transaction regardless of rollbacks, which is why they are commonly used as "recursion guards" to track if a trigger has already fired.

Other options are incorrect due to the strict "stack" nature of savepoints. Savepoints must be rolled back in reverse chronological order; rolling back to an earlier savepoint invalidates any savepoints created after it (Option A). Furthermore, a savepoint variable is only valid within the specific execution context in which it was created. You cannot pass a savepoint reference across different trigger invocations or asynchronous boundaries (Option D). Finally, while the rollback itself isn't a DML statement, the operations performed between setting a savepoint and rolling back still count toward DML and CPU governor limits (Option C). Understanding that memory state (static variables) remains unchanged during a database rollback is essential for debugging complex transactional logic.

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