Answer:
10
Explanation:
You can use process of elimination for this question
Since one of the chord is drawn in and part on the radius is connected to it, that "part" radius bisects the chord
Therefore, the chord is 16 units long
Then the diameter must be even longer
The only option that works for the radius is 10 as the diameter would be 20
If the radius was 5, the diameter would be 10 which is less than the chord
If the radius was 6, the diameter would be 12 which is less than the chord