Final answer:
The protective measure that provides a conductive connection to the earth during electrical storms to prevent damage from lightning is called grounding, and A. Lightning rod is the correct answer.
Step-by-step explanation:
The term conductive connection to the earth which acts as a protective measure refers to the process of grounding. Grounding is important for safety during electrical storms or in the presence of electrical equipment to prevent accidental electric shocks or damage. The correct answer to the question is A. Lightning rod, as it is designed to be a conductor with sharply pointed ends that safely collect and dissipate excess charge from a building into the earth during an electrical storm. Unlike an insulator, which does not allow electric charge to flow freely, a grounded conductor provides a path for the electricity to follow, thereby neutralizing potential differences and reducing the risk of a lightning strike causing damage.