An Art Therapist Observes That Mr

An art therapist observes that Mr. Miller is less agitated on days when art therapy is scheduled and more agitated on days when no art therapy is scheduled. She reviews the nursing charts and finds that her observation is confirmed by daily physiological and behavioral assessments recorded by the staff. Is she conducting a valid form of research?

A) Yes, because she has a record of repeated measurements over time that shows a confirming pattern, which she can further test to rule out rival hypotheses.
B) No, because she does not have a control, and without a larger sample she cannot predict that art therapy is causing Mr. Miller's change in behavior.
C) Yes, because clinical observations are more valid than experimental designs in showing the effects of art therapy.
D) No, because she doesn't know how other clients are responding to art therapy and they may be more or less agitated than Mr. Miller.