What inhibits the operation of a three-point seatbelt?

Your answer is correct because all three factors can interfere with the proper function of a three-point seatbelt. Wearing a thick winter coat can create slack and prevent the belt from fitting snugly, reducing its effectiveness in a crash. Passing the belt under both arms is dangerous because it bypasses the proper placement across the chest and pelvis, increasing injury risk. Not fully locking the belt into the buckle means the belt may come loose during an accident, failing to restrain the occupant properly. For maximum safety, the belt should lie flat, cross the chest and pelvis, and be securely latched.