In humans, approximately how much total blood volume does the average adult have?

• A. About 20 liters (approximately 18–22 L)
• B. About 1 liter (approximately 0.5–1.5 L)
• C. About 10 liters (approximately 9–12 L)
• D. About 5 liters (approximately 4.5–6.0 L)

Answer: (D)

Verified step by step guidance

1. Understand that the total blood volume in an average adult human is a physiological parameter that varies based on factors such as body size, sex, and overall health.
2. Recall that the average adult human blood volume is typically measured in liters and is often approximated for general understanding.
3. Recognize that the commonly accepted range for total blood volume in an average adult is about 4.5 to 6.0 liters, which is roughly 7-8% of total body weight.
4. Compare the given options to this known physiological range to identify the correct estimate.
5. Conclude that the option stating 'About 5 liters (approximately 4.5–6.0 L)' aligns with the standard physiological data for average adult human blood volume.