6. a biologist hypothesizes that restricting food from mice will decrease their activity. he designs an experiment in which he observes the activity of 50 mice under restricted food regimens. which of he following is true about his study?

a. the study is well designed since it uses a large sample of mice.
b. the study does not include a control group.
c. the study includes too many variables.
d. the results will allot the biologist to draw a valid conclusion.