Mathilde's unhappiness at the beginning of "The Necklace" is due primarily to a conflict between A
what she wants and what her husband wants.

B
what she has now and what she used to have.

C
what she wants and what she can afford to have.

D
what she deserves and what her husband thinks she deserves.

Your answer is C.

This is why:

So, Mathilde is very disappointed with how poor she and her husband are. We can tell by how she lusts and longs for the things she cannot afford. She longs to have these nice things, but cannot have them. She longs to be rich, but she is just simply not.

Hope this helps :)