Which of the following is an important component of cathodic protection?

• A. Sacrificial Anode
• B. Impressed current anode
• C. Protective coating
• D. Ground bed

Answer: (A)

Cathodic protection works by making the protected metal act like a cathode, so its tendency to oxidize (corrode) is greatly reduced. In a galvanic CP system, a sacrificial anode—made from a more electronegative metal placed in electrical contact with the structure—will corrode first, supplying electrons to the structure and pulling its potential to a level that minimizes corrosion. This sacrificial anode is the key element that actually provides the protective current in this setup.

Other items mentioned fit into CP in different ways or as supporting features. An impressed current anode is part of a separate CP method that uses an external power source to drive protection. A protective coating reduces the rate of corrosion by isolating the metal from the environment, and a ground bed is simply the arrangement where the anodes are buried or submerged. But the sacrificial anode is the essential component that directly enables protection in the common galvanic approach.