The correct option is B Box with 27 candies
They should buy the box of candies in which the number of candies can be divided equally among 3 people. That is, the number of candies should come in the table of 3 or be divisible by 3.
So out of the given options only 27 is divisible by 3.
27 ÷ 3 = 9
So, each will get 9 candies.