Atoms are the smallest unit of non-living things and CELLS are the smallest unit of living things.
The answer you are looking for is:<span>capillary beds</span>
Answer:
Option C
Explanation:
Option
A. 6440 mL/min
B. 4340 mL
C. 3500 mL/min
D. 2940 mL/min
Solution
It is required to find the minute ventilation which is equal to the product of rate of breathing and the total amount of gas being inhaled or exhaled per breathe. Let this minute ventilation be denoted by "
"
Thus,

where TD is the tidal volume and Br is the rate of breathing
Substituting the given values we get

We will now reduce the air held in the conducting zone of respiratory system
Air held per breathe 
Total Air held

Amount of fresh air one can breathe in and out every minute

Hence, Option C is correct