If Trying to Sway a Colleague into Using Cooperative Learning

If trying to sway a colleague into using cooperative learning in his classroom, which of the following would not be valid research conclusions you might use to help him to more positively perceive this instructional method?

A) Cooperative learning addresses all student academic hang-ups.
B) Cooperative learning has improved achievement.
C) Cooperative learning has increased student motivation.
D) Cooperative learning works across different grade levels.