Surgery Necrosis of the entire skin thickness and variable thickness of underlying subcutaneous tissue is: A 1st degree frostbite. B 2nd degree frostbite. C 3rd degree frostbite. D 4th degree frostbite. 💡 Explanation Necrosis of the entire skin thickness and variable thickness of underlying subcutaneous tissue is: ✓ Correct Answer: C. 3rd degree frostbite.