23. A dog breeder can determine that the sudden

appearance of hairlessness in one of the puppies

is a mutation if the dog

(1) is still hairless after 5 years

(2) shows no change in the hairless condition

after its diet is changed

(3) develops other conspicuous differences from

the parent

(4) is bred and the trait is capable of being

inherited

(4) is bred and the trait is capable of being  inherited

Explanation:

Mutation generally refers to a sudden change to the DNA sequence in the genome of an organism.

Since, DNA is the molecules responsible for heredity and the inheritance of traits by offspring from their parents, a mutation should be inheritable.

Hence, if a sudden appearance of hairlessness in one of the puppies is observed by a dog breeder, he/she can effectively conclude that the situation is caused by a mutation if the affected dog is bred with another dog and the hairlessness is observed in any of the resulting progeny.

Option 4 is the correct option.

b. the carbon cycle ensures living things have a source of hydrogen