Lactose is made of:

Options

A. `alpha`-D -glucose only
B. `alpha`-D-glycose and `beta`-D-glucose
C. `alpha`-D-glactose and `beta`-D-glucose
D. `beta`-D-galactose and `alpha`-D-glucose

Answer

C

Explanation

Lactose (milk sugar) is a dissaccharide, obtained by condensation of one molecule of `beta`-D-galactopyranose and one molecule of `beta`-D-glucopyranose.