Jack is planning an experiment to see how temperature can affect the reproduction rate of a certain species of bacteria.

Jack is listing some of the variables that could affect the outcome of the experiment. Which of the following variables should be included on his list?
A.
food Jack eats, day of week, number of pages in log book
B.
time of day, color of walls in lab, Jack's height
C.
temperature, light level, species of bacteria
D.
time of year, clothes Jack wears, Petri dish mass