Examine the parameter setting in your database: Which statement is correct about the database?（）

• A、Automatic memory management is disabled because PGA_AGGREGATE_TARGET and SGA_TARGET are not set
• B、The instance is started but the database will not be opened until PGA_AGGREGATE_TARGET and SGA_TARGET are set
• C、The database is opened but users cannot perform transactions until PGA_AGGREGATE_TARGET and SGA_TARGET are set
• D、Automatic memory management is enabled and, as per policy, 60% of the memory for System Global Area (SGA) and 40% of the memory for Program Global Area (PGA) will be distributed at startup