Scientists studying the effects of two different diets monitored three groups of people for one year. The first group was not asked to change the way they ate. The second group followed Diet A. The third group followed Diet B. The first group was asked not to change their diets in the study because —

Which of the following matches the organisms described with the correct domain? a. archaea--multicellular, eukaryotic organisms that do not have cell walls b. eukarya--single-celled and multicellular organisms, with a defined nucleus and a variety of nutritional sources c. bacteria--unicellular, eukaryotic organisms with cell walls that do not contain peptidoglycan d. bacteria--unicellular, eukaryotic organisms that always lack cell walls