Which statement about the DATA1 tablespace is true?

Your database is running in ARCHIVELOG mode. You are performing a user-managed
backup of the DATA1 tablespace. You place the DATA1 tablespace in backup mode by
issuing the following statement: ALTER TABLESPACE data1 BEGIN BACKUP;
While you are performing the backup, an error occurs that causes the instance to terminate
abnormally.
Which statement about the DATA1 tablespace is true?

A.
The DATA1 tablespace is automatically taken out of backup mode when the instance
aborts.

B.
If you restart the database, the DATA1 tablespace will be automatically taken out of
backup mode when the database is opened.

C.
If you restart the database, the DATA1 tablespace will be automatically taken out of
backup mode when the database is mounted.

D.
If you restart the database, the database will not be opened.

Explanation:
After database instance failure, the BEGIN BACKUP option would not obtain the tablespace
online, it will be OFFLINE mode. so that the instance cannot load the database file online.