<u>Answer:</u>
The Answer is <em><u>Option D. </u></em>
<em>Exchange of respiratory gases, oxygen and carbon dioxide take place in the alveoli of the lungs. Oxygen which is inhaled from the atmosphere diffuses through the walls of the alveoli and reaches to the adjacent capillaries into the red blood cells.</em>
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Answer: C
Explanation: Left ventricle. With the thickest muscle mass of all the chambers, the left ventricle is the hardest pumping part of the heart, as it pumps blood that flows to the heart and rest of the body other than the lungs.
Usually enzyme inhibitors slow down the enzymes activity, so in this case, I would put D.
