Final answer:
The safest action when seeing lightning while exercising outside is to head indoors immediately.
Explanation:
If you see lightning while you are outside exercising, the safest action is to head inside immediately. Lightning can strike far from the storm, so precautions are necessary. Avoid staying under a tree or lying in the grass as these actions increase your risk of being struck by lightning.
Learn more about lightning safety precautions here:
https://brainly.com/question/29793032
