A teacher interested in determining the effect of a new computer program on learning to read conducted a study. One hundred students were randomly assigned to one of two groups. The first group used the computer program while the second group did not. Both groups were tested to determine how much their reading levels improved. The results for the two groups were compared. What kind of study is this?

• This is an experiment because a treatment was applied to a group.
• This is an experiment because students were able to choose which group to join.
• This is a survey because students were randomly assigned to groups.
• This is a survey because a treatment was applied to both groups.