Following are the structures of `D-(+)-` glucose and `D-(+)-` galactose:
Which of the following statement is correct about these compounds?

Options

A. Both are components of lactose
B. They are diasteremers
C. They are C -4 epimers
D. All the above correct

Answer

D

Explanation

Lactose is composed of `beta-D` - glucose and `beta - D`- glucose
`D - (+) -` glucose and `D - (+) -` galactose are diasereomers as they are not mirror images of each other. They are epimers because they differ in their configuration only at one carbon atom, `C - 4`.