Answer:
The correct option is B. 35
Explanation:
Juan is making a fruit salad. He has grapes, watermelon, apples, pineapple, bananas, mangoes, honeydew, and cantaloupe
Number of fruits in total available to make fruit salad = 8
Number of fruits needed to make fruit salad = 5
No. of choices available for 1st fruit , watermelon is must = 1

Hence, In 35 ways he can make the fruit salad if it must contain watermelon
Therefore, The correct option is B. 35