Answer:
B: The gravitational pull of the Sun keeps the planets from leaving their orbits.
Explanation:
Gravity is the force by which a planet or other body draws objects toward its center. The force of gravity keeps all of the planets in orbit around the sun.
C. To live in a group with other organisms
The number of protons in the nucleus of the atom.
Phylogenetic species concept (PSC) The concept of a species as an irreducible group whose members are descended from a common ancestor and who all possess a combination of certain defining, or derived, traits (see apomorphy). ... "phylogenetic species concept." A Dictionary of Biology. .
Or
The biological species concept has its limitations (although it works well for many organisms and has been very influential in the growth ofevolutionary theory). ... In thisexample, Ensatina salamander lineages A and B are separate species.Each has a common ancestor that individuals of other species do not.
I hope that this helps you out
B. requires flowers.
Sexual reproduction is one type of biological reproduction wherein the genitals of the male and female organisms engage into a sexual activity in order for the sperm cells to fertilize the egg cells of the females.
In the case of most plants, they engage in asexual reproduction. Asexual reproduction happens outside the body system of a cell.
Moreover, this process is extrinsic than its opposite the sexual reproduction which happens in the female reproductive system.