Identify the reason the instance failed to start.

To implement Automatic Management (AMM), you set the following parameters:When you try to start the database instance with these parameter settings, you receive the following error
message:

SQL > startup
ORA-00824: cannot set SGA_TARGET or MEMORY_TARGET due to existing internal settings, see alert log
for more information.
Identify the reason the instance failed to start.

A.
The PGA_AGGREGATE_TARGET parameter is set to zero.

B.
The STATISTICS_LEVEL parameter is set to BASIC.

C.
Both the SGA_TARGET and MEMORY_TARGET parameters are set.

D.
The SGA_MAX_SIZE and SGA_TARGET parameter values are not equal.

Explanation:
Example:
SQL> startup force
ORA-00824: cannot set SGA_TARGET or MEMORY_TARGET due to existing internal settings
ORA-00848: STATISTICS_LEVEL cannot be set to BASIC with SGA_TARGET or MEMORY_TARGET