Final answer:
The correct approach to training a dog to turn on a light using shaping is by rewarding successive approximations of the desired behavior, beginning with looking at the switch and culminating in turning it on by command.
Step-by-step explanation:
The best way to train Sean's dog to turn the light on using the concept of shaping would be option (c): to reward his dog when the dog looks at the light switch, when she touches the light switch, when she pushes it, and when she turns it on by command. This method implements shaping by reinforcing successive approximations of the target behavior, rewarding the dog for actions that increasingly resemble the final desired action. Each step is an achievable approximation towards the complete behavior of turning on the light.