Which of the following is a major air pollutant?
A. carbon dioxide
B. zinc
C. copper
D. hydrogen peroxide

carbon dioxide

it is the right answer that i think

A B and C

Explanation:

Crossing over breaks, exchanges and rejoins chromosomes at corresponding points so introduces genetic variation. Because of crossing over offspring has characters of both parents.

Also independent assortment means that during separation of the chromosomes in anaphase, any chromosome can pair up with another. So for example if we have one parent plant with yellow and wrinkled seeds and other one with green and round seeds, then the gene responsible for round seed can pair up with either of the genes responsible for yellow seeds or green seeds. Hence the characters of offspring differ from the parents, it can have yellow round seeds or yellow wrinkled seeds and so on.

Mitosis will only produce 2 daughter cells which are exactly like their parent cells and are also identical to each other. Binary fission is a form of Asexual reproduction so it does not involve shuffling of genes from 2 parents.

Because of fertilization of egg with a sperm the maternal genes and paternal genes mix together. So it also produces genetic variations.