Inertia is hard to witness on earth because:
a. magnetism is much stronger
b. gravity and friction are always acting on objects.
c. our mass is too small

Option B

Explanation: This question refers to why we can not see the inertia caused by the movement of the Earth on us.

This would be because the force of gravity and friction is always acting on us, so we move along with the Earth because the gravity keeps us "glued" to the surface of the earth, and the friction of the surface impulses us to move along with the planet, and we move as one.

So the correct option is B

what is the actual question though?