A flagstaff 17.5 m high casts a shadow of length 40.25 m.The height of the building,which casts a shadow of length 28.75 m under similar conditions will be :	Choose the correct answer.
A) 10 m  B) 12.5 m  C) 17.5 m  D) 21.25 m  E) none

Rationale: "let height of the building be x meters 40.25 : 28.75 : : 17.5 < = > 40.25 x x = 28.75 x 17.5 x = 28.75 x 17.5 / 40.25 x = 12.5 answer : option b"
Answer: B