Here are the four postulates of natural selection, according to Charles Darwin:
1. variability - refers to different mutations that create different species
2. heritability - refers to the genes that are passed from one organism onto its descendants
3. overproduction of offspring - refers to the fact that more "children" is born than dies
4. natural selection - refers to those organisms that survive because they adapt to their surroundings better than those who will die
the answer is D. The amount of salt added
DescriptionNitrification is the biological oxidation of ammonia or ammonium to nitrite followed by the oxidation of the nitrite to nitrate. The transformation of ammonia to nitrite is usually the rate limiting step of nitrification. Nitrification is an important step in the nitrogen cycle in soil.