Which two are true about upgrading Data Guard environments consisting of one logical standby database running on a separate host from the primary?

A query on the view DBA_LOGSTBY_UNSUPPORTED on your primary database returns no rows.
As a result of this, you decide that an upgrade may use logical standby databases.
Which two are true about upgrading Data Guard environments consisting of one logical standby database running on a separate host from the primary?

A.
The upgrade always requires downtown until the upgrade of the logical standby is completed.

B.
Using manual upgrade, catctl.pl can be executed in some cases on the primary and standby database simultaneously.

C.
The upgrade always required downtime until the upgrade of the primary is completed.

D.
Using manual upgrade, catupgr.sql needs to run on the primary database only.

E.
SQL Apply on the local standby database must be stopped while the primary database is upgraded.

F.
Fast-Start Failover can be used to protect the primary database during the upgrade.

Explanation:
B (not D): Oracle Database 12c introduces the new Parallel Upgrade Utility, catctl.pl. This utility replaces the catupgrd.sql script that was used in earlier releases.
Although you can still use the catupgrd.sql script, it is deprecated starting with Oracle Database 12c and will be removed in future releases. Oracle recommends
database upgrades be performed with the new Parallel Upgrade Utility, catctl.pl.
E: Once the database is started in upgrade mode, only queries on fixed views execute without errors until after the catctl.pl script is run.

https://docs.oracle.com/database/121/UPGRD/upgrade.htm#UPGRD52867
https://docs.oracle.com/database/121/UPGRD/deprecated.htm#UPGRD60034