$A$ molecule of glucose reacts with $X$ molecules of phenylhydrazine to form osazone. Determine the value of $X$.

Sucrose is a

Identify the monomer of starch.

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?

Which one of the following is a polysaccharide?

In a patient's urine test,diabetes can be detected using...........