Which of the following statements is $CORRECT$ about saccharic acid?

What is the product formed when glucose reacts with an excess of $C_6H_5-NH.NH_2$?

Four carbohydrates: glucose,lactose,sucrose,and starch are present. Different tests are carried out with these $4$ carbohydrates separately. The following observations are made:
$(a)$ Heated: It is charred.
$(b)$ $I_2$ solution: No violet colour.
$(c)$ Fehling solution: Reddish brown precipitate is observed.
$(d)$ It does not reduce copper$(II)$ acetate to $Cu_2O$. No red precipitate is observed in $5 \ min$.
Which carbohydrate satisfies all the above observations?

What is maltose composed of?

Identify the trisaccharide from the following.

Glycosidic linkage between $C_{1}$ of $\alpha$-glucose and $C_{2}$ of $\beta$-fructose is found in.