I believe the answer is Capillaries
D is the answer can I be marked as brainiest
<span>By their nature, they can be either "good" (beneficial) or "bad" (harmful) for the health of plants, humans, and other animals that come into contact with them. A virus is acellular (has no cell structure) and requires a living host to survive; it causes illness in its host, which causes an immune response.Bacteria are alive, while ...</span><span>
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