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: Microbiology
Which is always present in bacteria ? 
Select and explain. 
A. Cell wall, B. Cytoplasmic membrane, C. Mitochondria, D. Nucleoli
B: Cytoplasmic membrane
Answer: B: Cytoplasmic membrane 
Explanation: Ans. b. Cytoplasmic membrane