The correct answer is: A. Road pavements.
Plastic bitumen is a type of bitumen that is heated to a high temperature and then mixed with other materials, such as sand or gravel, to create a paving material. It is a very durable material that can withstand heavy traffic and weather conditions. Plastic bitumen is often used in the construction of new roads, as well as in the repair and maintenance of existing roads.
Option B, expansion joints, are used to prevent cracks in concrete structures. They are typically made of a flexible material, such as rubber or plastic, and are installed between sections of concrete that are likely to move or expand.
Option C, crack fillings, are used to repair cracks in concrete structures. They are typically made of a material that is similar to the concrete itself, and are applied to the crack to fill it in and prevent it from getting wider.
Option D, none of these, is incorrect. Plastic bitumen is a type of bitumen that is used for road pavements.