Stuart has a felony conviction and is not allowed to possess or own a firearm. However, he feels he needs a gun for protection and enlists the aid of his friend, Milo, to purchase a firearm for him. Milo does not know about Stuart's felony conviction but is more than happy to purchase the gun for Stuart and give it to him after the same is completed. So$,$ Milo goes to a local gun show to purchase the weapon and give it to Stuart later. This is an example of:

Demand side intervention

Gun show loophole

Straw purchase

Supply side intervention