Task: Question Answering
Input (English): Question: The average (arithmetic mean) of the 5 positive integers k, m, r, s, and t is 10, and k < m < r < s < t. If t is 20, what is the greatest possible value of the median of the 5 integers?

 Option A: 16

 Option B: 18

 Option C: 13

 Option D: 20

 Option E: 22
Output (English): Option C