What do you infer from this?

View the Exhibit to examine the output produced by the following query at three different times
since the database instance started and has experienced workloads of different capacities:
SQL> SELECT substr(component, 0, 10) COMP, current_size CS, user_specified_size US
FROM v$memory_dynamic_components
WHERE current_size!=0;
What do you infer from this?

A.
The database instance is running with manual PGA management.

B.
The database instance is running with manual shared memory management.

C.
The database instance has the MEMORY_TARGET value set to a nonzero value.

D.
All sessions are connected to the database instance in dedicated mode, and no RMAN or
parallel query operations have been performed.

Explanation:
MEMORY_TARGET specifies the Oracle system-wide usable memory. The database tunes
memory to the MEMORY_TARGET value, reducing or enlarging the SGA and PGA as needed.
In a text-based initialization parameter file, if you omit MEMORY_MAX_TARGET and include a
value for MEMORY_TARGET, then the database automatically sets MEMORY_MAX_TARGET to
the value of MEMORY_TARGET. If you omit the line for MEMORY_TARGET and include a value
for MEMORY_MAX_TARGET, the MEMORY_TARGET parameter defaults to zero. After startup,
you can then dynamically change MEMORY_TARGET to a nonzero value, provided that it does
not exceed the value of MEMORY_MAX_TARGET.