A lion is hunting a zebra. The lion sneaks up on the prey and begins to run towards the zebra as it approaches is 50 meters between the animals. At the same time, the zebra begins to run away from the lion. If the zebra runs at 55 km / h, and the lion runs at 80 km / h, how long does it take before the lion catches the zebra? A: 2.0 s B: 7.2 s C: 9.1 s D: 13 s