The table below summarizes the ages of students in a club. There are 21 students in the club.
| Age (years) | Number of students |
|---|---|
| 10 to 12 | 5 |
| 13 to 15 | 6 |
| 16 to 18 | 7 |
| 19 to 21 | 3 |
Which of the following could be the median age of the students in years?
12
14
17
20
