I think it is C because i got this same exact question in my class
Answer:
The answer is W. chloroform-chloroform and acetone-acetone interactions are stronger than chloroform-acetone interactions. This is because the bond between acetone-acetone is a dipole-dipole interactions and chloroform-chloroform dipole-dipole compared to the weaker hydrogen-bonding between acetone-chloroform.
It turns out that this hydrogen-bonding happens to be stronger the original dipole-dipole forces, so this shows NEGATIVE DEVIATION from Raoult's law.
