In this task, you are given a question and answer options for that question. Using this information, you have to classify each text into different topics: medicine, nursery, psychology, chemistry, pharmacology, biology.

[Q]: Question: One of the components of injectable formulations are preservatives. This category includes different excipients with different mechanisms of action. Which of the following is used as a chelating agent ?: 
 Options:  <0> Butylhydroxyanisole. <1> Ethylenediaminetetraacetic acid. <2> Ascorbic acid. <3> Propyl gelate <4> Tocopherol.
[A]: pharmacology


[Q]: Question: For the care of the nipple cracks during lactation it is recommended: 
 Options:  <0> Washed with water and neutral pH soap after each feeding. <1> Spread a few drops of milk and let air dry after the tetada. <2> The use of healing ointments. <3> 70º alcohol applied through sterile gauze between shots. <4> Apply cold between shots.
[A]: nursery


[Q]: Question: The kidneys secrete the hormone: 
 Options:  <0> Calcitriol. <1> Renina <2> Angiotensin II. <3> Aldosterone <4> Calcitonin
[A]:
biology