The dimensional formula for entropy is

Explanation:
Entropy is a measure of randomness or disorder of a system.
It’s formula is
S= QT ( where S is entropy, Q is energy in the system, T is the Temperature)
 S.I. unit is JK-1 = kgm2s-2K-1
Dimensional formula is given as [M L2 T-2 K-1]

Final answer:
Hence the correct option is C, i.e. [M L2 T-2 K-1].