GMAT Question of the day

Define x∇y by the equation x∇y = xy − y . Then 2∇ 3 =
(A) 1
(B) 3
(C) 12
(D) 15
(E) 18

From the above definition, we know that x∇y = xy − y .
So we replace x with 2 and y with 3 in the definition:

2∇3 = 2 ⋅ 3 − 3 = 3 .

Hence, the answer is (B).