The correct option is B increase water repellent properties of bitumen
Polyblend is a powdered form of recycled modified plastic that was developed by the company owned by Ahmed Khan of Bangalore. He proved that mixing polyblend along with bitumen (a petroleum based semi-solid substance obtained from distillation of crude oil), increased the water repellant properties of bitumen. Thus, this blend of polyblend and bitumen was used to lay down roads in Bangalore and the road life increased by a factor of three.