The answer is spontaneous mutation .
Sometimes genes, for no known reason(s), change their form in a process called spontaneous mutation.
Mutation is the actually the alteration of the nucleotide sequence of the genome of an organism, virus, or other genetic elements permanently.
Spontaneous mutation : It is a process in which gene automatically for no reason change their form.
Of these options, I'd say the third choice or "Many species of organisms that lived long ago are now extinct". I hope this helps :)
Answer:
The properties of elements will repeat periodically when the elements are arranged by their atomic number.
Explanation:
I think it is B) 18 but you'd have to check. Help?
