A. Mass extinction is the answer
A control group is sort of the normal group. The group you aren't changing or messing with. It is to show what the species/experiment acts like on its own in response to something without you having to change it at all.
With an experimental group, you are changing something about the subject before putting it in the conditions it will need to respond to.
I don't entirely understand, but I know the control group is constant, unchanging. It sort of helps with distinguishing things. I have examples of experiments if that will help you understand what a control group is to answer the question. I also have a The Death Cure example if you have seen or read the book. I hope you do not fail this assignment, but even if I did not answer with an answer you were looking for, it could have helped you answer the question on your own.
I saw somewhere a similar question, though I was given the answer choices. If this is the answer you are looking for: variable(s).
Control groups don't use variables because you aren't changing them.
Technically A and B, but A is more true, so it is the 'correct' answer.
Answer: The correct answer is- D certain factors are dominant and other factors are recessive.
Mendel was interested in knowing the offspring that is produced from the cross pollination (that is from two different plants) as he wanted to study different traits of pea plant.
For doing so, he first removed the anthers of one plant (to prevent self pollination) and then transferred the pollens of one plant into the stigma of another plant.
When he allowed the cross pollination of purebred pea plant with other plant, he observed that some factors are dominant (such as tall height of pea plant, which masks the expression of recessive factors) and other are recessive (such as dwarf height of pea plant).
Thus, option D) is the right answer.
