What is the purpose of this?

The line set noexec_user_stack= l should be added to the /etc/system file to prevent an
executable stack while executing user programs. What is the purpose of this?

A.
help prevent core dumps on program errors

B.
help programs to execute more quickly by keeping to their own memory space

C.
log any messages into the stack log

D.
help make buffer-overflow attacks more difficult