<h2><u>Answer</u> :</h2>
The correct option is A. If a dominant allele is present, the recessive allele won’t be seen.
The dominant allele is the one which appear, and the recessive one isn't shown.
For example - If a person has 2 alleles of eye colour as B ( black ) and b ( brown ), in which black is dominant and the brown one is recessive, then the person will have black eye colour because only dominant allele shows its characteristics.
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Surface waves cause most the the damage
Flu vaccination can help you from getting sick with flu. Vaccine reduces the risk of infection by working with body’s natural defenses to help them safely develop immunity to diseases. If you get sick, flu vaccine will make your illness milder.
The right answer is A mutation.
Alteration of the genetic material (DNA or RNA) of a cell or virus that causes a change in certain traits due to the inheritance of this genetic material from generation to generation.
Abnormal modification of the DNA of a gene, either spontaneously during cell division, or under the influence of external agents called mutagens. This gene is modified to be transmitted to the daughter cells. Some mutations have no effect on the cell. Others are the first step in a long process of cancerization.
Rare are the mutations that are beneficial.