Question

in good experiments, there are two groups: the experimental group and the control group. almost everything about these groups should be the same. for example, if you are testing how feeding fish food to walruses affects their weight, all of your walruses should receive the same amount of exercises, live in the same type of walrus tank, be the same age, etc. all these things that are kept the same between the experimental group and the control group are called controlled variables. in the above example, which of the following would be controlled variables? whether or not you feed fish food to the walruses (some will get fish food and some wont) the size of the habitat that the walruses live in. both the age of the walruses in the experiment and the size of the habitat that the walruses live in. the age of the walruses in the experiment

Explanation:

Controlled variables are kept the same in experimental and control groups. The age of walruses and size of habitat are mentioned as things to be the same. Whether feeding fish - food is the independent variable being tested.

Answer:

C. Both the age of the walruses in the experiment and the size of the habitat that the walruses live in.