Out of the choices given, the mechanisms that drives evolution is natural selection. The correct answer is B, natural selection.
Fixation
Nitrogen is converted from atmospheric nitrogen (N2) into usable forms, such as NO2-, in a process known as fixation. The majority of nitrogen is fixed by bacteria, most of which are symbiotic with plants. Recently fixed ammonia is then converted to biologically useful forms by specialized bacteria
To solve this problem on genetic dominance, we will need a punnet square.
Let's let P represent purple-flowered and p represent white-flowered.
We have one purple flowered plant with the alleles PP, and we have one white flowered plant with the alleles pp. Using a punnet square, we can determine the alleles of the offspring.
<u>P</u> <u>P</u>
p| Pp Pp
p | Pp Pp
As we can tell from our punnet square, all of our offspring will have purple flowers. This is because the purple-flower allele is dominant and the white-flowered allele is recessive.
Since each flower has a dominant and recessive allele, they are heterozygous.
Therefore, the solution to this problem is D.
They are alike because they are the simplest form of life and the carry genetic information.