ICM represents the momentum of inertia of the solid sphere about an axis passing through its center of mass whereas I represents the momentum of inertia of the solid sphere about an axis passing through a point which lies at a distance d from its center of mass. Using parallel axis theorem,
I=ICM +Md2
This equation suggests that the momentum of inertia about any axis passing through a point other than its center of mass is greater than ICM .
⟹ ICM is the least moment of inertia that a body can have.
Hence \(I=\frac{2}{7}MR^2\) cannot be the moment of inertia of the solid sphere.