According to the Code of Federal Regulations (46 CFR) for Tank Vessels, what is the minimum allowable flashpoint for a fuel to be burned in a steam boiler?

Correct Answer: Option C — 140oF

46 CFR 58.01-10 mandates that fuel oil used in steam boilers must have a minimum flashpoint of 140°F (60°C). This safety requirement minimizes the risk of explosive vapors forming in the fuel system or storage tanks, which is essential for fire prevention in machinery spaces.