(A)

Here is a dependency between U and X so there must be 2 stall

Here is a dependency between V and W so there must be 2 stall

(B)

Here is a dependency between U and X so there must be 2 stall

Dependency between V and W there is one stall

(C)

Here is a dependency between V and U so 2 stalls

Here is a dependency between U and X so 2 stalls

Here is a dependency between X and Y so 1 stall

(D)

Dependency between T and Y so 1 stall

So from all of them, answer should be D because of less number of stalls