With no explanation, label text_A→text_B with either "DON'T KNOW", "NO" or "YES".
text_A: Bao Tong, Zhao Ziyang's aide, was the highest-ranking official to be formally charged with a crime connected with 1989 demonstrations. He was convicted in 1992 of "revealing state secrets and counter-revolutionary propagandizing" and served seven years in prison. To purge sympathizers of Tiananmen demonstrators from among the party's rank-and-file, the party leadership initiated a one-and-a-half-year-long rectification program to "deal strictly with those inside the party with serious tendencies toward bourgeois liberalization". Four million people were reportedly investigated for their role in the protests. More than 30,000 Communist officers were deployed to assess the "political reliability" of more than one million government officials. The authorities arrested tens if not hundreds of thousands of people across the country. Some were seized in broad daylight while they walked in the street; others were arrested at night. Many were jailed or sent to labor camps. They were often denied access to see their families and often put in cells so crowded that not everyone had space to sleep. Dissidents shared cells with murderers and rapists, though torture during interrogations was practically unheard of.
text_B: In addition to the terrible conditions, is it reasonable to conclude that police forces in China at this time used both the threat of and the occurrence of torture as a deterrent to crime?
NO.