Answer : 1. "20"
Explanation :

Answer: A) 20 Explanation: 6 choose 3 means number of possible unordered combinations when 3 items are selected from 6 available items i.e, nothing but 6C3. Now 6C3 = 6 x 5 x 4/3 x 2 x 1 = 120/6 = 20.