Explanation

This problem is about permutations, because the order of the figurines matter since they each look unique.

You have two cases to consider here. Start with the option that Margaret buys three witches and three ghosts. In that case, she has 3 choices of witch for the first spot, 3
choices of ghost for the second spot, 2 choices of witch for the third spot, 2 choices of ghost for the fourth spot, 1 choice of witch for the fifth spot, and 1 choice of ghost for the sixth spot:

Hence, her total number of arrangements is 3 × 3 × 2 × 2 × 1 × 1 = 36, which is choice (C). If she buys four of each figurine, her number of arrangements is 4 × 4 × 3 × 3 × 2 × 2 × 1 × 1 = 576, choice E.

Hence options C and E are correct!
_________________

3!*3!=36
4!*4!=576
ans C & E

Hello from the GRE Prep Club BumpBot!

Thanks to another GRE Prep Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.