Which of the following should be done to prevent further attacks of this nature?

An administrator notices the following file in the Linux server’s /tmp directory.
-rwsr-xr-x. 4 root root 234223 Jun 6 22:52 bash*
Which of the following should be done to prevent further attacks of this nature?

A.
Never mount the /tmp directory over NFS

B.
Stop the rpcidmapd service from running

C.
Mount all tmp directories nosuid, noexec

D.
Restrict access to the /tmp directory