Task: Question Answering
Input (English): Question: A can fill tank in 9 minutes, B can empty the tank in 18 minutes.. In what time the tank be filled, if both pipes work simultaneously?

 Option A: 14 minutes

 Option B: 15 minutes

 Option C: 16 minutes

 Option D: 17 minutes

 Option E: 18 minutes
Output (English): Option E