Use reasoning to lead to the answer of the following question:
A 600 meter long train crosses a signal post in 20 seconds. How long will it take to cross a 3 kilometer long bridge, at the same speed?\nOptions:\n(A) 4 min\n(B) 2 min\n(C) 8 min\n(D) 9 min\n(E) 5 min

(B)
S = 600/20 = 1530 mps\nS = 3600/30 = 120 sec = 2 min.

The answer: (B)