The correct option is B JK−1
We know that,
Heat capacity =ms
where s is specific heat capacity
& m is the mass of the substance.
Now, heat lost or gained is given by,
Q=msΔT
⇒ms=Q(J)ΔT(K)
∴ we can say that,
unit of heat capacity =J/K
Thus, option (b) is the correct answer.