Answer;
Antibodies.
The human immune system fights infection by releasing antibodies.
Explanation;
The immune system acts to defend the body against pathogens such as viruses, bacteria and fungi that may cause a disease.
It does so using various types of mechanism, one is by the production of antibodies.
Antibodies are proteins that are produced by the B-cell and are used by the immune system to identify and neutralize pathogens.
These antibodies also activates proteins known as complements which assist in the killing of bacteria, viruses and the infected cells.
A tornado is a violently rotating column of air extending from the base of a thunderstorm to the ground, often made visible by a condensation funnel. The formation of tornadoes<span> is complicated. So the answer would be A
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Intense exercise seems to prevent muscle loss and preserve rmr most effectively: mostly, and physically exacting task that A. Incorporates many muscle group and B is done near your maximum heart rate modify. Feel free to make your own intense exercise.
Answer: Stars?
Explanation: I think it is stars because there is only one star in our solar system. I don't know for sure if it is, but I think it is. Don't be too sure of my answer.