This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General anatomy, Subject name: Anatomy
The membrane rich in protein is: 
Select and explain. 
A. Inner mitochondrial membrane, B. Outer mitochondrial membrane, C. Endoplasmic reticulum, D. All
A: Inner mitochondrial membrane
Answer: A: Inner mitochondrial membrane 
Explanation: Of all the membranes inner mitochondrial membrane is rich in protein content