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: Skin
The "angry back" phenomenon is related to ONE of the following: 
Select and explain. 
A. Patch test, B. Prick test, C. RAST, D. Desensitization
A: Patch test
Answer: A: Patch test 
Explanation: It refers to the non specific false positive patch test positive reactions when the test is done during active dermatitis. It is also called Excited skin syndrome.