Answer:
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Explanation:
All three have sacs known as alveoli just beneath their plasma membranes.
Their is AB, O, B, and A. Which is four. If your were to include whether the blood type was a Negative blood type and positive blood type they're would be . AB+, O+, B+, A+, AB-, O-, B-, A-. Which is eight.
Answer: The answer is the last option, Backflow of blood through a defective valve.
Explanation: Hypotension causes high blood pressure, and the other two options are not related to heart murmurs. A hear murmur is when the blood isn't flowing in the right direction causing the hear to beat irregularaly.
The answer for this question should be D) or the fourth option Protists.