You will be given a definition of a task first, then some input of the task.
In this task, you are given a multiple-choice question about healthcare. Answer the question based on your information and classify your answers into '1', '2', '3', and '4'.

Question: The kidneys secrete the hormone: 
 Options:  <1> Calcitriol. <2> Renina <3> Angiotensin II. <4> Aldosterone <5> Calcitonin
Output:
1