Data Sufficiency - 39

If *triangle* denotes one of the four arithmetic operations addition, subtraction, multiplication and division, what is the value of 1 *triangle* 2 ?

(1) n *triangle* 0 = n for all integers n.
(2) n *triangle* n = 0 for all integers n.

Answer: B

From statement (1): *triangle* can be both positive or negative as

n-0 = n
n+0 = n

Hence insufficient

From statement (2): *triangle* can only be negative in this case as

n-n = 0

Hence sufficient