Anaerobic respiration<span> in muscles. Glucose is not completely broken down, so much less energy is released than during </span>aerobic respiration<span>. There is a build-up of lactic acid in the muscles during vigorous exercise. The lactic acid needs to be oxidised to carbon dioxide and water later. Hope this helps!</span>
World population stops growing
<span>Hippocrates believed that there are four humors in human body which need balance for a healthy being. These were:
Blood, phlegm, yellow bile, and black bile.</span>
Galen expanded the idea of the humors and introduced four temperaments which were these:
choleric (hot / dry), melancholic (cold / dry), sanguine (warm / moist), and phlegmatic (cold / moist).
Another expansion Galen did was that he gave each humor/temperament physical and psychological qualities and said that even the food items have an association with the certain humor, those foods can effect certain humor in certain ways.
The Earth was first considered habitable when we discovered that it was Microbial organisms that started the process. I would go with D.