If a researcher wants to use a control group whose participants receive a placebo pill as well as an experimental group whose participants receive a new treatment medication, which type of statistical test is MOST appropriate for analyzing the results and why?
single sample t- test; it is a single-sample, within-groups design
paired-samples t test; it is a single-sample, between-groups design
independent-samples t test; it is a two-sample, within-groups design
independent-samples t test; it is a two-sample, between-groups design