Answer:
A. Interferons
Explanation:
According to Wikipedia, "Interferons are a group of signaling proteins made and released by host cells in response to the presence of several viruses. In a typical scenario, a virus-infected cell will release interferons causing nearby cells to heighten their anti-viral defenses."
<span>Wash your hands. Do it frequently and especially
after using the toilet, changing a diaper or petting an animal and
before handling or eating food.
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