Concept:Semisynthetic polymers are obtained by chemically modifying naturally occurring polymers.
Explanation:Polymers are classified into three categories based on their origin.
Natural polymers exist in nature, such as wool, silk, and natural rubber.
Synthetic polymers are entirely man-made through chemical processes, such as nylon and polyester.
Semisynthetic polymers are natural polymers that are chemically treated to improve their properties.
Dacron is a completely synthetic polyester fibre, so it is not semisynthetic.
Nylon 6 is a fully synthetic polyamide fibre, so it is not semisynthetic.
Wool is a natural protein fibre obtained from animals, so it is a natural polymer.
Cellulose nitrate is prepared by treating natural cellulose with nitric acid.
Because it retains the cellulose structure but is chemically modified, cellulose nitrate is a semisynthetic polymer.
Therefore, among the given options, cellulose nitrate is the correct choice.
Answer:D. Cellulose nitrate