Multiple partners, monogamous relationship, unprotected sex
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.
<span>Antiretroviral therapy</span>
As people progress into old age, their disease-fighting immune systems become reduced.
<h3>The effects of aging on immune system</h3>
Immune system is the major system of the body that protects the body against invading disease causing microorganisms. It is made up of,
- proteins (antibodies) and
As an individual advances in age, the efficiency of the immune system, which is it's ability to fight diseases, would reduce.
This is because the production of white blood cells, antibodies and chemicals are equally reduced.
Therefore, as people progress into old age, their disease-fighting immune systems become reduced.
Learn more about immune system here:
brainly.com/question/15975169