Ace the Phlebotomy Tech Challenge 2026 – Stick It to the Test and Succeed!

Plasma is the liquid component of blood and makes up about 55% of the total blood volume. In this case, the question is asking specifically about the percentage of water in plasma. Water makes up about 90% of plasma, making option C the correct answer. The other options are incorrect because they either underestimate (75%, 80%) or overestimate (95%) the percentage of water in plasma. Option D may seem close to the correct answer, but it is important to remember that plasma is not pure water, and the remaining 10% includes other substances such as proteins, electrolytes, and nutrients. Therefore, the correct answer is C 90%.