They share a more recent common ancestor.
Answer:
Moves down the concentration gradient
Explanation:
Since diffusion moves materials from an area of higher concentration to an area of lower concentration, it is described as moving solutes "down the concentration gradient" (compared with active transport, which often moves material from area of low concentration to area of higher concentration...
Well, carbohydrates burn and release energy. Nucleic acids give identity (like DNA, RNA). Lipids also give energy, but it's more difficult (they must be first turned into carbohydrates first). Proteins are building blocks for the cells.
Now, knowing all of this should make it easy to choose the correct answer :)