Answer:
An Experiment
Explanation:
To understand and explain the natural events, the scientific method is followed which refers to the systematic approach to understand the work. A scientific experiment is one of the step of the scientific method which is used to test the predicted statement which could explain the event.
The experiment includes the observations related to the predicted hypothesis and to answer the scientific question. The observation can produce facts which could prove or disprove the hypothesis.
Thus, an experiment is the correct answer.
The link between the two is that they both can cause headaches and sores from the body. Since anxiety affects the body mentally it can also affect it physically too.
The third option. Long period of uninterrupted low or moderate intensity physical activity.
Depressants is the answer
