The commonest disaccharide has the molecular formula

The incorrect statement from the following with respect to carbohydrates is:

Which one among the following chemical tests is used to distinguish monosaccharide from disaccharide?

Which of the following is the structure of $\beta-D$-Glucopyranose?

What is the number of primary and secondary alcoholic groups respectively present in glucose?

From the following, the correct statements about polysaccharides are:
$(I)$ Starch is a polymer of $\alpha-D(+)$-glucose.
$(II)$ Amylose component of starch is not soluble in water.
$(III)$ Amylose is a branched chain polymer of $\alpha-D(+)$-glucose.
$(IV)$ Cellulose is a straight chain polymer of $\beta-D(+)$-glucose units.