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: Biochemistry
Signal peptides are synthesized in 
Select and explain. 
A. ER, B. Free ribosomes, C. Membrane bound ribosomes, D. Golgi body
C: Membrane bound ribosomes
Answer: C: Membrane bound ribosomes 
Explanation: None