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
GABA- B receptor is which type of receptor - 
Select and explain. 
A. Inotropic receptor, B. Metabotropic transmembrane receptor, C. Ligand gated ion channel, D. Intrinsic ion channel
B: Metabotropic transmembrane receptor
Answer: B: Metabotropic transmembrane receptor 
Explanation: Ans: B. Metabotropic transmembrane receptor(Ref : KDT //e p. 399, 402 6 6h/e p. 395; Katzung 17th/e p' 377-378; lP/e p' 355)Metabotropic recePtors:Are G-protein coupled receptors which act through second messenger.Examples: GABA-B receptors, Muscarinic (M1 to M5)