Final answer:
ACE inhibitors are used to treat hypertension, heart failure, and diabetic nephropathy. However, they are not used to treat hypotension.
Step-by-step explanation:
ACE inhibitors are used in the treatment of hypertension, heart failure, and diabetic nephropathy. Therefore, the correct answer is c. Hypotension. ACE inhibitors are typically used to reduce blood pressure by blocking the enzyme ACE, which converts angiotensin I to angiotensin II. By reducing the production of angiotensin II, ACE inhibitors help to relax and widen blood vessels, improving blood flow and reducing blood pressure.