What is the minimum requirement for securing roll-off and hook containers?

Secure to the rear of the vehicle with at least one of the following three mechanisms: Rear Mechanism 1: One tiedown attached to both the vehicle chassis and the container chassis. Rear Mechanism 2: Two tiedowns installed lengthwise, each securing one side of the container to one of the vehicle's side rails. Rear Mechanism 3: Two hooks, or an equivalent mechanism, securing both sides of the container to the vehicle chassis at least as effectively as the tiedowns in the two previous items.