If c is 25% of a and 50% of b, what percent of a is b?
Options:	A) 2.5 %	B) 50 %	C) 25 %	D) 35 %	E) 250 %

Rationale: "answer = b 25 a / 100 = 50 b / 100 b = 25 a / 50 = 50 a / 100 = 50 %"
Answer: B