which value to implement automatic PGA memory management?

Which parameter must be set to which value to implement automatic PGA memory management?

A.
Set memory_target to zero.

B.
Set STATISTICS_LEVEL to BASIC.

C.
Set pga_aggregate_target to a nonzero value.

D.
Set pga_aggregate_target and sga_target to the same value.

E.
Set sgajtarget to zero.

Explanation:

Reference:
http://docs.oracle.com/cd/B28359_01/server.111/b28310/memory004.htm#ADMIN11233