Scarlett Is a Graduate Student Who Is Observing Children Playing

Scarlett is a graduate student who is observing children playing together after watching a film. She knows that some children saw a film that contained graphic scenes of violence and some children saw a non-violent film, but she doesn't know which film each child she is observing watched. What would we call this type of procedure?

A) correlational
B) blind
C) confounded
D) unethical