Task: Question Answering
Input (English): Question: Machines A and B produce bottles at their respective constant rates. Machine A produces k bottles in 2 hours and machine B produces k bottles in 5 hours. How many hours does it take machines A and B, working simultaneously, to produce 14k bottles?

 Option A: 14

 Option B: 16

 Option C: 18

 Option D: 20

 Option E: 22
Output (English): Option D