Frostbite is defined as:

• A. A reversible numbness due to cold but not freezing.
• B. Frostbite occurs when skin or tissue freezes.
• C. An irreversible deep tissue frost injury.
• D. A heat-induced skin rash.

Answer: (B)

Frostbite is defined by tissue damage that occurs when skin and underlying tissues actually freeze due to exposure to extreme cold. That freezing of the tissue is the defining feature, which is why this description fits best. It helps distinguish frostbite from frostnip, a milder, reversible condition where cold causes numbness but the tissue hasn’t frozen. The other descriptions aren’t correct: frostbite isn’t defined by irreversibility in all cases ( severe frostbite can cause permanent damage, but the key cause is freezing), and it isn’t related to heat-induced skin problems.