Which three statements are true about Global Sequences when connected to a physical standby database with Real-Time Query enabled?

Which three statements are true about Global Sequences when connected to a physical standby database with Real-Time Query enabled?

A.
If the CACHE option is set then the size of the cache must be at least 100.

B.
Their creation requires that a LOG_ARCHIVE_DEST_n parameter be defined in the standby that points back to their primary.

C.
Their usage will always have a performance impact on the primary database.

D.
Their usage may have a performance impact on the physical standby database if the CACHE size is too small

E.
They must have the NOORDER and CACHE options set.

Explanation:
B: the terminal standby should have a LOG_ARCHIVE_DEST_n parameter defined that points back to the primary.

D: Because the standby’s requests for a range of sequences involve a round-trip to the primary, be sure to specify a large enough value for the CACHE keyword
when you create a sequence that will be used on an Oracle Active Data Guard standby. Otherwise, performance could suffer.
E: In an Oracle Active Data Guard environment, sequences created by the primary database with the default CACHE and NOORDER options can be accessed
from standby databases as well.

https://docs.oracle.com/database/121/SBYDB/manage_ps.htm#SBYDB5164