EXPLAIN WHY it is most appropriate for the study. a) Is the aspirin produced by a particular pharmaceutical company better than that of a competitor at relieving headaches?

) Select the study that is most appropriate and EXPLAIN WHY it is most appropriate for the study.
a) Is the aspirin produced by a particular pharmaceutical company better than that of a competitor at relieving headaches? Which of the following would best be used to study this: 1) a case-controlled observation; 2) an observation; 3) a double-blind experimental procedure; and 4) and experimental procedure.