Which of the following hexoses will form the same osazone when treated with excess phenyl hydrazine?

Step-by-step solution

Osazone formation involves the reaction of the first two carbon atoms of a sugar with phenylhydrazine. Sugars that differ only in the configuration at the first and second carbon atoms (epimers at C-2) form the same osazone. D-glucose, D-fructose, and D-mannose share the same configuration at carbons C-3, C-4, C-5, and C-6. Specifically, D-glucose and D-mannose are C-2 epimers, and D-fructose is a ketose that, upon reaction with phenylhydrazine, undergoes tautomerization to form the same intermediate as D-glucose a