Insulin is a protein hormone, so the pair "Insulin – Protein" is correctly matched.
Inulin is a polysaccharide (a fructan made of fructose units), so the pair "Inulin – Polysaccharide" is correctly matched.
Cellulose is a polymer (a polymeric carbohydrate), so the pair "Polymeric substance – Cellulose" is correctly matched.
Uridine consists of the base uracil linked to ribose sugar, which makes it a nucleoside, not a nucleotide.
A nucleotide is a nucleoside with one or more phosphate groups, e.g., uridine monophosphate (UMP).
Hence, the mismatch is "Uridine – Nucleotide".
Therefore, the correct option is the one with option B.
