What is the best defense against Local DoS attacks?

A.
patch your systems.
B.
run a virus checker.
C.
run an anti-spy software.
D.
find this program and kill it.
E.
None of the choices.
Explanation:
Local DoS attacks can be a program that creates an infinite loop, makes lots of copies of itself, and continues
to open lots of files. The best defense is to find this program and kill it.