In hull welding, thick sections or high carbon content require preheating to reduce hydrogen cracking and improve weld quality. This statement is most accurately described as:

• A. A general welding guideline with no practical basis
• B. A precise metallurgical requirement only for aluminum hulls
• C. A recommended practice for controlling hydrogen-related cracking in thick sections
• D. An outdated rule with no current relevance

Answer: (C)