B. Intensity.
Hope this helps.
Answer:B
Explanation:
Because you want to increase the oxygen intake as much as possible.
Explanation:
Their husbandry of sheep, goats and cattle grazing in fertile valleys across the region provided a stable, balanced diet, and allowed the Khoikhoi to live in larger groups in a region previously occupied by the San, who were subsistence hunter-gatherers.
If Cindy wanted to increase her endurance by taking supplements or drugs, she would be attempting to increase THE UPTAKE OF OXYGEN BY RED BLOOD CELLS
D because its chewing tobacco which is extremely addictive