A client checks and rechecks the lock on the door five times before leaving home. What statement by the client indicates that this behavior is a result of obsessive-compulsive disorder (OCD) ?

Checks and rechecks the door lock 5 times before leaving the house

Explanation:

He checked the lock 5 times to be sure he did locked door. "5" times here is extensive, at least a maximum of 3 times of checking before leaving I. e if he had a lot to do and he just needed to be sure.

The act of him checking more than 3 times is an sign obsessive compulsive disorder.