Which statement is true in this situation?

You are in the middle of a transaction updating a very important table. The machine on which a database was running reboots because of power outage. This caused a database instance failure.
Which statement is true in this situation?

A.
The online redo log files and archived redo log files are required to accomplish the recovery

B.
The uncommitted transaction will be committed at the next startup of the database instance

C.
The uncommitted transaction is rolled back automatically at the next opening of the database

D.
The DBA has to perform the recovery on the database to recover the uncommitted transaction