What is the primary function of the head gasket, and which symptoms best indicate its failure?

What is the primary function of the head gasket, and which symptoms best indicate its failure?

• A. Regulates engine oil pressure to protect bearings.
• B. Maintains proper pistonring lubrication throughout the engine.
• C. Seals the head to the block to prevent coolant/oil leakage and maintain cylinder compression.
• D. Acts as a barrier to intake air.

Answer: (C)