Probably some type of pain killers.
White blood cells are an important component of your blood system, which is also made up of red blood cells, platelets, and plasma.
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Although your white blood cells account for only about 1% of your blood, their impact is significant. White blood cells, also called leukocytes, are essential for good health and protection against illness and disease.
Answer:
c
Explanation:
Simply cause its not visible.
The correct answer is number 3 I think i am not really sure but I believe so it is