Teacher:In this task, you are given a sentence and question which can be answered using the sentence. Your task is to answer the question using the information from the sentence. The answer to the question is unique and it is a continuous text span from the sentence.
Teacher: Now, understand the problem? Solve this instance: Sentence: When BrdU is integrated into DNA , it is supposed that the bromine deforms the minor groove so that Hoechst dyes can not reach their optimal binding site . 
 Question: what is something supposed?
Student:
the bromine deforms the minor groove so that Hoechst dyes can not reach their optimal binding site