Most of a cell's molecules can be classified as belonging to one of four major classes: lipids, carbohydrates, nucleotides, or amino acids. Classify the five molecules into one of the four major classes.

Diagram, in attachments

Explanation:

From the left side of the screen to the right,that is from a structure with a sugar structure with two other molecules  attached to it.

The first molecular structure is Nucleotides. Reasons it contains the middle ribose sugar(5-carbon)connected to the phosphate group and  Nitrogenous bases.This is the structure of nucleotides  and when this is joined by phosphodiester bond between one a nucleotide, to the phosphate group of another  nucleotide molecule  it forms a nucleic acid molecule.

The second structure from left to right with  long carbon chains, it is  a lipid.That js an Ester formed from the reaction of fatty acids with alcohol glycerol.

However, the presence of Phophate group in structure makes it different from a normal tryglycerides.The phosphate group has replaced  one of the  the three fatty acid molecules.Therefore it is called Phospholipid.With one hydropholic ends(phosphate ends) and the hyrophobic end the  carbon chain,with one unsaturated. The lipids molecules are held together my ester bonds.

The next structure is the protein structure(dipeptide).Genrally amino acid is made up of the central Alpha carbon connected on the right by the Carbonyl group(coo-) on the left by the Amine(NH2) group.The R-group which determines the type of amino acids  and hyrdogen atom.In the above structure condensation reaction  has occurred between the hydrogen atom  of  the amine group and carbonyl group of the other amino unit to form a dipeptide.The  bond formed from the condensation is the peptide bond.

The last structure on the far right are the carbohydrate -ring structure and the straight chains.The functional groups of the CHO  -Carbonyl group and hydroxyl group are glues to this.

a and c are the answeres