Detailed Instructions: In this task, you are given a sentence. You are expected to recognize the name of gene or protein. Although there might be several correct answers, you need to write one of them.
Q: To assess the safety of the angiotensin converting enzyme inhibitor enalapril a multicenter , open , randomized , prazosin - controlled trial was designed comparing the incidence and severity of symptomatic hypotension on the first day of treatment .
A:
angiotensin converting enzyme