Which of the following fibre is made of protein?

Silk Cotton Nylon Rayon

Silk

The correct answer is option 2. Silk Cellulose is a kind of carbohydrate that is present in cotton. Silk from the domesticated silkworm consists of a single core protein, termed fibroin. The synthetic fibers Rayon and Nylon aren't formed of proteins, but rather a combination of various chemicals.