In order to prevent galvanic corrosion, an aluminum boat must be insulated from the davits and gripes. Which of the following is acceptable as an insulator?

Correct Answer: Option A — Hard rubber

Hard rubber possesses the necessary dielectric properties and mechanical durability to physically isolate aluminum lifeboat hulls from steel davits and wire gripes, preventing direct metal-to-metal contact and stopping destructive galvanic corrosion as mandated by marine engineering standards.