Flammable liquid means any liquid which gives off flammable vapors at or below __________.

Correct Answer: Option B — 80°F (26.7°C)

Under 46 CFR 30.10-22, a flammable liquid is defined as any liquid that gives off flammable vapors (as determined by flashpoint) at or below 80°F (26.7°C). These liquids are categorized into Grades A, B, and C based on their specific volatility.