What are his observations? We can’t answer this without knowing his observations if those are the conclusions. Please provide the rest of the information and I can answer.
Answer:
Ideally, the experimental and control groups are identical. As much as possible, the two groups should overlap in every characteristic.
Explanation:
At the beginning of your study, you need your two groups to be as statistically similar as is humanly possible. That way, when you control for other variables, you can reasonably attribute any statistically significant differences at the end of the study to your intervention.
Technically, the black widow spider is the deadliest spider despite it's size, due to it's overwhelmingly potent venom, which can and will kill a human if no medical attention is sought out for the person bit.
General Westmoreland was the chief commanding officer during the Vietnam War. After his tenure Creighton Abrams took over.
<h2>B) option is correct </h2>
Explanation:
Natural selection is a selection pressure which operates in a population and allow the best fitted genotype to survive in changing environmental conditions and eliminate the other genotype which are not fit
In artificial selection, breeders select superior breed for the breeding purpose so that this type of selection favors the superior genotype and eliminates inferior genotype, thus leading to genetic drift
Stabilizing selection is a type of natural selection in which intermediate genotype is favored but extreme genotypes (inferior and superior) are eliminated
In the given example of pigmentation in pigeons, breeding is selectively done with intermediate pigmentation hence intermediate genotypes will be favored