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: Pharmacology
Which of the following serotonergic receptors is an autoreceptor ? 
Select and explain. 
A. 5–HT1A, B. 5–HT1B/1D, C. 5–HT2A, D. 5–HT3
A: 5–HT1A
Answer: A: 5–HT1A 
Explanation: None