A man standing 150 m away from a cliff fires a gun. A second man who is standing 300 m further away from first man hears the gun 1 second after he sees the flash. The second man will hear the echo from the cliff _______.
(A) 1 second after seeing the flash
(B) 2 seconds after hearing the gun
(C) 2 seconds after seeing the flash
(D) 4 seconds after hearing the gun