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
Relcovaptan is ? 
Select and explain. 
A. Angiotensin antagonist, B. Renin inhibitor, C. Vasopressin antagonist, D. ACE inhibitor
C: Vasopressin antagonist
Answer: C: Vasopressin antagonist 
Explanation: Ans. is'c'i.e., Vasopressin antagonistVasopressin receptor antagonists (Vaptans)At V1A receptor - RelcovaptanAt V1B receptor - NelivaptanAt V2 receptor - Lixivaptan, sotavapton, tolvaptan, mozavaptanNon-selective - Conivapton