Which of the following sugars is the sweetest?

The number of chiral carbons in $\beta-D-(+)$-glucose is

Assertion : Treatment of $D$-glucose with dilute alkali affords an equilibrium mixture consisting of $D$-mannose,$D$-fructose and starting substance $D$-glucose.
Reason : The reaction involves an intermediate in which hybridization of $C_2$ changes from $sp^3$ to $sp^2$.

What is the chemical formula of cellulose?

Identify the glycosidic linkage present in lactose.

$C_2$-epimer of $D$-Glucose is