[A] : Keratin is one of a group of fibrous in- soluble proteins (scelero proteins) found in ectodermal cells of animals, as in hair, horns and nails. Leather is almost pure keratin.
[R]: Cornification is a process occurring in vertebrate epidermis and epidermal struc- tures in which keratin replaces the cytoplasm of a cell.

Options

A. If both A and R are true and R is the correct explanation of A
B. If both A and R are true but R is not the correct explanation of A
C. If A is true and R is false
D. If both A and R are false

Answer

B