"exposure to something" sounds awkward to Koreans and I also have a hard time understanding it. What exactly does it mean like in this case?

gu112)It has long been taken as common knowledge that people prefer media messages that support their views...The hypothesis was shown to be correct, the students choosing to read articles that supported their views 58% of the time. Time permitting, many students did ty try to balance their exposure by reading article written from both friendly and unfriendly perspectives...