The "reaction" force does not cancel the "action" force because:

Explanation

Newton's Third Law of Motion states: For every action, there is an equal and opposite reaction. This means that when two objects interact, the forces they exert on each other are equal in magnitude and opposite in direction, but importantly, they act on different objects, which prevents them from canceling each other out. Option B is correct because it aligns with this principle. Option A is incorrect because it suggests inequality in forces, which contradicts the law. Option C is incorrect as it mistakenly implies the forces are in the same direction. Option D is incorrect because it wrongly suggests that the forces do not occur simultaneously.