Select one study from A, B, C. Thanks!

For each of the following, identify if an experiment or an observational study is to be conducted: A) In order to discover which of 4 weight loss programs gets the best results, subjects are randomly selected to each of the programs. [ Select ] B) In order to find out which graduates have the highest starting salaries, we gather information from graduates of ivy league, private, and public universities. [ Select ] C) A delivery company that owns a fleet of trucks performs a study to determine whether rotating tires at specific intervals has any effect on the number of miles a set of tires lasts. [ Select ] [ Select ] Observational Study Experiment