How many different pairs of numbers (s, t) such that s = 3t can be obtained if s and t are selected from the set of number {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12}  Choose the correct answer: A) 1 B) 2 C) 3 D) 4 E) 5

Rationale: given s = 3 t t can take 0,1 , 2,3 , 4 and so s = 0,3 , 6,9 , 12 4 such pairs can be formed . answer e
Answer: E