20、 Which is true about the SYSTEM and SYSAUX tablespaces?

A) The SYSAUX tablespace can be made read-only but the SYSTEM tablespace cannot.

B) Both tablespaces can be used for temporary storage if no temporary tablespace is defined.

C) Only the SYSTEM tablespace contains data dictionary tables.

D) Both tablespaces must be online for a database to be accessible.

Answer:A