Which of the following is considered to include organisms that are most closely related?

Its family,but the actual answer should have been SPECIES
since the definition of species is : A species is often defined as the largest group of organisms capable of interbreeding and producing fertile offspring.

B. Family.

The answer is family

Kings Play Chess On Fiber Glass Stools

Therefore, B) Family, is correct.

King Phillip Came Over For Great Soup. so B) Family.