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: Medicine
Drug used in heart failure -a) ACE inhibitorsb) Hydralazinec) Carvedilold) Chlorthalidone 
Select and explain. 
A. acd, B. bcd, C. abc, D. abd
C: abc
Answer: C: abc 
Explanation: None