B, because as energy is move up form the phyramid, energy is lost.
The answer for your question is C
The answer is <span>d. homologous structures.
Homologous structures are </span><span>similar structures shared by different species. For example, the anatomy of joints in bones of birds and dinosaurs, support the idea that these two groups have a common ancestor. But since these two groups are different enough to be separated into different classes, it can be concluded that they evolved from the common ancestor.</span>
umm . this answer is not complete .
Its a nucleotide.
This is the answer because they are the basic units of nucleic acids. These nucleotides are made up of a pentose sugar, a nitrogenous base, and a phosphate group.