In your multitenant container database (CDB) containing pluggable database (PDBs), you
granted the CREATE TABLE privilege to the common user C##ADMIN in root and all PDBs.
You execute the following command from the root container:
SQL > REVOKE create table FROM C##ADMIN;
What is the result?
A. It executes successfully and the CREATE TABLE privilege is revoked from C##ADMIN in root only.
B. It fails and reports an error because the CONTAINER=ALL clause is not used.
C. It excludes successfully and the CREATE TABLE privilege is revoked from C##ADMIN in root and all PDBs.
D. It fails and reports an error because the CONTAINER=CURRENT clause is not used.
E. It executes successfully and the CREATE TABLE privilege is revoked from C##ADMIN in all PDBs.
Answer: A
Explanation: 在多租户环境里面，REVOKE…FROM…命令默认缺省选项为 container=current ，也就是回收当前容器数据库的权限。题目告知是在根容器（CDB$ROOT）里面执行的语句，因此只会回收根容器的权限。知识拓展如下图
原文地址：https://www.cnblogs.com/askscuti/p/12672339.html