The best summary of Newton's laws is:
a. Newton's 1st Law: Balanced Forces & Inertia
Newton's 2nd Law: Unbalanced Forces & Fnet = ma
Newton's 3rd Law: action/reaction force pairs
This option correctly describes each of Newton's laws, with the first law focusing on inertia and balanced forces, the second law explaining the relationship between force, mass, and acceleration with unbalanced forces, and the third law highlighting the concept of action and reaction.