Recall the experiment on ant navigation. To run a controlled experiment, what parameters were held constant for the test group of 75 ants?

All variables except leg length (and therefore stride length).

Explanation:

The ant navigation demonstrates the different movements of the ants. The ants generally navigate based on the sun's rays and the availability of the food in a particular direction.

Scientists can perform the different experiments to find navigation in ants. Different parameters and objects can be used for the identification of the ants navigation. The length of the ants must be keep constant and all other variables can be changed.

Thus, the correct answer is all variables except leg length.