Answer:
Static-group comparison design
Explanation:
Based on the information provided within the question in regards to the situation at hand it can be said that the design that was used was a Static-group comparison design. This research design focuses on studying two separate groups, one of which is given the treatment while the other is not. The results are then compared with one another to come to a conclusion. This is what Ryan did, which in this scenario the group that received the "treatment" was the group that got to play with Ryan, since that is what he is trying to study.