This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Surgery
Pregangrene is 
Select and explain. 
A. Ulceration, B. Hyperaesthesia, C. Putrefaction, D. Mummification
B: Hyperaesthesia
Answer: B: Hyperaesthesia 
Explanation: Pregangrene is changes in tissue which indicates that blood supply is inadequate to keep tissues alive and presents with rest pain, colour changes, oedema, hyperaesthesia.