You will be given a definition of a task first, then some input of the task.
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.

Question: The ascorbic acid esters are used in Pharmaceutical Technology as: 
 Options:  <0> Reducers <1> Blockers <2> Synergists <3> Chelators <4> Antiseptics
Output:
pharmacology