Read the article's Introduction (paragraphs 1-2). Which sentence from the Introduction suggests that scientists and video game companies rarely work together on research?

A. Oxford university researchers conducted a study on how playing video games affects the mental health of game players.

B. For a long time, scientists have been hoping to better understand how playing video games impact people.

C. They wanted to understand the effects of video games on behavior and the feeling of well-being.

D. However, a lack of transparency from game makers has been a challenge.