In case the factor of safety against sliding is less than 1.5, a portion of slab is constructed downwards at the end of the heel slab, which is known

In case the factor of safety against sliding is less than 1.5, a portion of slab is constructed
downwards at the end of the heel slab, which is known as

(A) A key

(B) A cut-off wall

(C) A rib

(D) All the above

The correct Answer Is
(D) All the above