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.

Sentence: As ex-slaves risked beatings for failing to meet the continuing duties , their freedom was limited . 
 Question: what was  limited?
their freedom

Sentence: The `` power cepstrum '' was defined in a 1963 paper by Bogert et al. . 
 Question: when was something defined?
1963

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 will  be integrated  into something?

BrdU