Giving points for the answer

the correct answer is - (C) if it is a recessive allele - carriers will have that allele in their genome but not express the lethal form of the gene

Explanation:

for example chicken pox stays in your body your entire life after you have it once, and comes back when your'e old, in the form of shingles.

affects the water bodies: excessive use of fertilizers causes eutrophication. the fertilizers which are used on plants affect the quality of land on which it is used, further causing erosion of soil. the fertilizers used on plants contain harmful chemical fumes which affect the environment.