If n is a positive integer and n^2 is divisible by 18, then what is the largest positive integer that must divide n?  Choose the correct answer:	A) 3	B) 4	C) 6	D) 8	E) 9

Rationale: "18 = 2 * 3 ^ 2 if 18 divides n ^ 2 , then n must be divisible by 2 * 3 = 6 the answer is c ."
Answer: C