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Automatic Shared Memory Management (ASMM) has been enabled for your database instance. The initialization parameters for the components that are managed by ASMM are not set. After observing the effects of ASMM, you executed the following command:
SQL> ALTER SYSTEM SET DB_CACHE_SIZE = 100M;
Which statement is true in this scenario?
A. The minimum memory size for the database buffer cache is set to 100 MB.
B. The maximum memory size that can be obtained by the database buffer cache during ASMM is set to 100MB.
C. The minimum memory size allocated for a server process in the database buffer cache in dedicated mode is set to 100 MB.
D. The maximum memory size from the database buffer cache that can be released for dynamic distribution during ASMM is set to 100 MB.

　　启用 ASMM 之前，应该从 SPFILE 中删除单个内存区参数，因为设置这些参数会使ASMM 受到限制。看到 ASMM 分配的效果之后，如果决定要调整特定组件的分配值，可以为这些组件指定值。如果指定的值比目前的值小，这些值将被视为各个组件的最小内存大小。如果指定的值比目前的值大，那么只要有空闲内存，就可以将内存组件的大小重新上调至您提供的值。执行此操作会限制可用于自动调整的内存量，但在环境需要对大小进行特殊调整、而 ASMM 又无法满足此需要时，可使用此功能。