Answer:
Correct answer is A
Explanation:
Cell theory is a theory, not a law because the cell theory does not have enough support to become a law.
Answer – 3. A weakened form of a virus
When getting a vaccination, the substance which is injected into the body is a weakened form of a virus. This weakened from of the virus has the ability to arouse the body’s defense mechanism without causing an infection.
<span>
</span>