View the Exhibit to examine the output produced by the following query at three different times sincethe database instance started and has experienced workloads of different capacities： SQL> SELECT substr（component， 0， 10） COMP， current_size CS，user_specified_size USFROM v$memory_dynamic_componentsWHERE current_size!=0； What do you infer from this（）
- AThe database instance is running with manual PGA management.
- BThe database instance is running with manual shared memory management.
- CThe database instance has the MEMORY_TARGET value set to a nonzero value.
- DAll sessions are connected to the database instance in dedicated mode， and no RMAN or parallelquery operations have been performed.