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
Angiotensin converting enzyme inhibitors are useful in congestive heart failure as: 
Select and explain. 
A. First choice drugs unless contraindicated, B. An alternative to diuretics, C. A substitute for digitalis, D. Adjuncts only in resistant cases
A: First choice drugs unless contraindicated
Answer: A: First choice drugs unless contraindicated 
Explanation: None