Jake has a very unusual problem. whenever he leaves his home, he has to check and recheck every exterior door and window several times before he can "feel comfortable." jake would probably be best diagnosed as suffering from

obsessive-compulsive disorder

Explanation:

Obsessive-compulsive disorder abbreviated as OCD is a mental disorder that is characterized by the person's need to perform a certain task repeatedly or has the need to obsess over a though repeatedly. A person suffering from OCD is not able to control himself from repeatedly performing those tasks or having those thoughts. Some of the common compulsive activities that a person suffering fro OCD performs are hand washing, checking to see if the door is locked, cleaning the surroundings, etc. Since Jake has this problem of checking the doors and the windows before leaving the home several times before he feels comfortable, he is suffering from OCD.

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