The molecules that are polymers among the options provided are:
a. cellulose - a polysaccharide made of glucose units, making it a polymer.
b. RNA - a polymer made of nucleotides.
c. polypeptide - a polymer made of amino acids linked by peptide bonds.
g. DNA - a polymer made of nucleotides.
The other options are not polymers:
d. amino acid - a monomer unit, the building block of proteins, but not a polymer by itself.
e. ATP - an individual nucleotide; it is not a polymer.
f. triglyceride - a lipid made of glycerol and fatty acids; it is not a polymer.
h. disaccharide - a carbohydrate made up of two monosaccharide units; it is not a polymer.
So the correct polymers are: a, b, c, and g.