What monomer is made up of a base, a sugar, and a phosphate group a. monosaccharide b. nucleotide c. phospholipid d. amino acid

The key in identifying monomers of biological macromolecules is to associate them together:

Monosaccharides are sugar units which make up carbohydrates
A base, a sugar (deoxyribose or ribose), and a phosphate group make up Nucleotides
Phospholipids aren't monomers of a macromolecule - they are the major constituents of cell membranes
Amino acids are the units which make up proteins

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The correct answer is a. we know this because n (hap) + n (hap) = 2n (dip).

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