Explanation/Reference:
Note: WebLogic Server provides three different options for staging files: stage mode, nostage mode, and external_stage mode.
* In stage mode, the Administration Server copies the deployment files from their original location on the Administration Server machine to the staging directories of each target server.
* In nostage mode, the Administration Server does not copy the archive files from their source location.
Instead, each target server must access the archive files from a single source directory for deployment.
The staging directory of target servers is ignored for nostage deployments.
* External_stage mode is similar to stage mode, in that target servers deploy using local copies of the deployment files. However, the Administration Server does not automatically copy the deployment files to targeted servers in external_stage mode; instead, you must copy the files to the staging directory of each target server before deployment.
Incorrect Answers:
C, D: In the external_stage and Nostage mode the Administration Server does not copy deployment files.
Reference: https://docs.oracle.com/cd/E13222_01/wls/docs81/deployment/concepts.html#1001124