$\beta-D$-Glucose and $\alpha-D$-Glucose are:

Under what conditions is glucose converted to gluconic acid and saccharic acid?

Identify glycosidic linkages for formation of chain and branches respectively in amylopectin.

What are the hydrolysis products of $(i)$ sucrose and $(ii)$ lactose?

Determine the $D$ and $L$ configuration for the carbohydrates shown in the image.

On prolonged heating with $HI$,glucose gives a compound '$C$',which can be obtained by Wurtz reaction using sodium metal and compound '$D$'. Identify '$D$'.