Which of the following compounds is obtained when glucose is heated with $HI$ for a long time?

$A$ sugar,that is not a disaccharide,among the following is

The 'epimerisation' involves

Glucose is a/an:

From the given following ($A$ and $B$) cyclic structures, those which will not react with Tollen's reagent are :

Glycogen is a branched chain polymer of $\alpha-D$-glucose units in which the chain is formed by $C_1-C_4$ glycosidic linkage,whereas branching occurs by the formation of $C_1-C_6$ glycosidic linkage. The structure of glycogen is similar to: