Which item is listed as a common method for introducing contraband that involves mail?

• A. Mail
• B. Books
• C. Drones
• D. Outside people throwing items over the fence

Answer: (A)

Introducing contraband through mail relies on the mail system as the delivery channel. Mail items, letters, and packages pass through a centralized process, and even with screening, contraband can be hidden inside or within mailed materials. Because mail is a routine, high-volume pathway, it’s a common way contraband can enter a facility. The question is asking for the method that involves mail, so this channel is the best fit. The other options describe different entry routes—drone drops or items thrown over the perimeter—so they don’t involve the mail system. Books can come by mail too, but the method in question is the mail channel itself, not the specific item.