Which is the water-insoluble component of starch?

Amylopectin

The correct answer is option 1. amylopectin.

Starch is a polysaccharide that is made up of two components: amylose and amylopectin. Amylose is a linear polymer of glucose molecules, while amylopectin is a branched polymer of glucose molecules. Amylopectin is the water-insoluble component of starch.

Amylose is soluble in water because it can form hydrogen bonds with water molecules. Amylopectin is insoluble in water because it is too branched to form hydrogen bonds with water molecules.

Cellulose is a different type of polysaccharide made up of glucose molecules. Cellulose is a linear polymer of glucose molecules, but it is different from amylose because the glucose molecules in cellulose are linked together in a different ways. Cellulose is also insoluble in water.

Therefore, the only option for the water-insoluble component of starch is amylopectin.

The other options are incorrect. Option (2) amylose, is the water-soluble component of starch. Option (3) cellulose, is a different type of polysaccharide that is also insoluble in water. Option (4) none of these, is incorrect because amylopectin is the water-insoluble component of starch.