C . True. A transaction that is interrupted by a system failure is automatically rolled back by Oracle to ensure data consistency. This is part of the ACID (Atomicity, Consistency, Isolation, Durability) properties that Oracle adheres to.
D . True. A ROLLBACK without specifying a savepoint rolls back the entire transaction and removes all savepoints within that transaction. This restores the data to the state it was in at the beginning of the transaction.