Answer:Genetic testing involves examining your DNA, the chemical database that carries instructions for your body's functions. Genetic testing can reveal changes (mutations) in your genes that may cause illness or disease.
Although genetic testing can provide important information for diagnosing, treating and preventing illness, there are limitations. For example, if you're a healthy person, a positive result from genetic testing doesn't always mean you will develop a disease. On the other hand, in some situations, a negative result doesn't guarantee that you won't have a certain disorder.
Explanation:
The mother actually gives more DNA to a baby more than the father because of the little organelles, aka the mitochondria that live inside your cells are only to be received from your mother.
But in DNA, it can vary who's side you can get more of, and in some rare cases, equally. This is because dominant genes carry out around 75% of the time and genes that are recessive can carry out 25% of the time, depending on the genetics of both the mother and the father. Example, brown eyes are a dominant gene over blue eyes, so there is a 75% chance that the baby will have brown eyes and a 25% chance that the baby has blue eyes if one parent has the brown eye gene and one has the blue eye gene.
I hope this helped!! :D
Your brain stem would be your answer
D. A struggle for existence is apparent.
If a struggle for existence is apparent, natural selection occurs because all of the weak/unfit/unadapted ones die.