Best biochemical description of glucose is?
(A) Exists as ketose sugar (B) Present in L form in all biosystems (C) Its C-4 epimer is galactose (D) It's a disaccharide
(C) Glucose:

Simple sugar (monosaccharides)
Has six carbon atoms (hexose)
Its C-4 epimer is galactose
Has 2 isomers - D-isomer (D-glucose/dextrose, occurs widely in nature) and L-isomer (L-glucose - does not occur much in nature)
It is stored as a polymer (in plants as starch and in animals as glycogen)