Correct Answer:
C. 6 litres
This question assesses basic knowledge of human anatomy and physiology, specifically concerning respiratory system capacities. Lung capacity refers to the total volume of air the lungs can hold.
- Correct Answer: C) 6 litres
The average total lung capacity for an adult human is approximately 6 litres (or about 6000 milliliters). This measurement includes the vital capacity (the maximum amount of air that can be exhaled after a maximum inhalation) and the residual volume (the amount of air that always remains in the lungs after a maximal exhalation). This capacity can vary based on factors like age, sex, height, and physical fitness.
- Incorrect Answers:
- A) 4 litres and B) 5 litres are generally underestimates for the average total lung capacity. While a person's vital capacity might be in this range, the total lung capacity is higher due to the inclusion of residual volume.
- D) 7 litres is typically an overestimate for the average adult. While some individuals, particularly very tall or highly athletic males, might have lung capacities approaching this, 6 litres is the most accurate average figure for the general adult population.