Which statement tells an advantage of multicellular organisms? A. All of the cells are the same.

B. They can form complex organ systems.

C. One cell performs all of the necessary functions.

D. They can reproduce quickly.

B. They can form complex organ systems

Explanation:

in 1859, charles darwin set out his theory of evolution by natural selection as an explanation for adaptation and speciation. he defined natural selection as the "principle by which each slight variation [of a trait], if useful, is preserved".

the answer is true when observing or determining population size, a direct observation is use, in which each organism is counted in a population or in an area. one benefit of this measure is that you get the exact population count but it will take a long time to  determine  the  size  of a  population.