The correct option is C 6
The number of ways in which he can put them is stacks such that all the stacks are of same height is nothing but the number of factors of 32.
Factors of 32: 1, 2, 4, 8, 16, 32
There are 6 factors of 32.
Therefore, there are 6 ways of putting them in stacks such that all the stacks are of same height.