Anthony places a drop of water under a microscope and observes some small objects. He concludes that the small objects are cells. Which choice most likely describes the evidence that Anthony saw?

It depends on the lens of the Anthony´s microscope, but It is likely that he saw artifacts

Explanation:

An optical microscope contains lenses of focal lenght that enable to see different structures. In this case, it is likely that Antony saw artifacts since living cells are not easy to focus with the optical microscope, it requires operator experience  

the solute can move "downhill," from regions of higher to lower concentration, relying on the specificity of the protein carrier to pass through the membrane. this process is called passive transport or facilitated diffusion, and does not require energy.

carbon atoms, hydrogen, oxygen, and nitrogen.