Final answer:
The restoring force of a spring is proportional to its displacement from equilibrium. When displaced by 2 cm to the left, the spring exerts a 4 N restoring force to the right.
Step-by-step explanation:
The restoring force of a spring is directly proportional to the displacement from its equilibrium position as defined by Hooke's Law, which is given by the formula F = -kx, where F is the force exerted by the spring, k is the spring constant, and x is the displacement. In this scenario, given that when the spring was displaced by 4 cm (0.04 m) to the right there was a restoring force of 8 N to the left, if we were to displace it by 2 cm (0.02 m) to the left, we would expect half the force since the displacement is halved, maintaining the direct proportionality. Therefore, the restoring force will be 4 N to the right, which matches option B in the set of given answers.