Final answer:
Zinc is the material used on most anode disks that is light, strong, and heat-resistant.
Step-by-step explanation:
The material used on most anode disks that is light, strong, and heat-resistant is zinc. Zinc is a silvery metal that quickly tarnishes to a blue-gray appearance. It is commonly used as a sacrificial anode to protect other metals from corrosion. Zinc is lighter than other materials such as lead and has a higher capacity as an anode.