A plant cell wall is mainly composed of:

Correct option is B

The correct answer is (b) cellulose.
· The plant cell wall is primarily made up of cellulose, a complex carbohydrate (polysaccharide) that provides structural support and rigidity to the cell.
· Cellulose molecules form a strong and fibrous network, giving the plant cell wall its characteristic strength.
· This structure allows plant cells to maintain their shape, resist mechanical stress, and regulate their growth.
· The plant cell wall also contains other polysaccharides, such as hemicellulose and pectin, as well as lignin in certain cell types, which adds additional rigidity.
Other Options:
· Lipid: Lipids are primarily found in the cell membrane, where they help form a barrier around the cell, but they are not the main component of the cell wall.
· Starch: Starch is a storage polysaccharide in plants, used as an energy reserve, but it is not a structural component of the cell wall.
· Protein: Although proteins are present in small amounts in the cell wall, they are not the primary structural material. Proteins mainly act as enzymes and structural components but do not form the main framework like cellulose.