What is the minimum WLL of each tiedown used to secure crushed or flattened vehicles?

Option 2:
Has containment walls on three sides that:
Extend to the full height of the load
Block against cargo movement in the forward, rearward, and one sideways direction.
Secures each stack of vehicles with a minimum of two tiedowns, each having a minimum WLL of 2,268 kg (5,000 lb.).
Option 3:
Has containment walls on two sides that:
Extend to the full height of the load.
Block against cargo movement in the forward and rearward.
Secures each stack of vehicles with a minimum of three tiedowns, each having a minimum WLL of 2,268 kg (5,000 lb.).
Option 4:
Has a minimum of four tiedowns per vehicle stack with each tiedown having a minimum WLL of 2,268 kg (5,000 lb.).