Use Least Common Multiple or Greatest Common Divisor to Solve

Multiple Choice

Use least common multiple or greatest common divisor to solve the problem.
-Two runners run around a circular track. The first runner completes a lap in 6 minutes. The second runner completes the track in 13 minutes. If they both start at the same place and the same time and Go in the same direction, after how many minutes will they meet again at the starting place?

A) 19
B) 156
C) 78
D) 79