A student measured the weight of 10 male rats fed junk food compared to 10 male rats fed a healthy diet. The average weight of each group can be seen in the table below. What important variable did the student hold constant when she designed this experiment?

Weight in ounces Weight in kilograms
Rats fed junk food 21.1 ?
Rats fed healthy food 16 ?


Multiple Choice

the conversion between ounces and kilograms

type of food

the sex of the rats

change in weight of the rats

1 answer

the sex of the rats