A train ]eaves from a station and moves at 40 km/hr. After 2 hours, another train leaves from the same station and moves in the same direction at a certain speed. lithe second train catches up with the first train in 4 hours, what is the speed of the second train?

A

55 km/hr

B

50 km/hr

C

60 km/hr

D

65 km/hr