When leveraging a heavy object to remove a survivor, remember to:
a. leave the cribbing in place after removing the survivor
b. stabilize the object with cribbing as you go
c. place your hands under the object to raise it
d. lift the object very rapidly and drop it to one side

B). Stablize the object with cribbing as you go.

Explanation: when leveraging an heavy object to remove a survivor, cribbing and leveraging is used together to stabilize the object, this is done by an alternative lifting of the object and placing crib materials underneath the lifted edge, whilst conducting the rescuing operations it is said that leveraging and cribbing at opposite ends should not be done together because doing that would increase instability of the object.

the two sets of lines are :

answer; (b) ; /stronger bonds between the nations of africa