Read the text below and decide which answer (A, B, C or D) best fits each gap.
Scientists have built a 300kph racing car that uses chocolate as a fuel! The project is (1) ………… to show how car-making could (2) ………… environmentally friendly. The car meets all racing car (3) ………… apart from its fuel. This is a mixture of waste chocolate and vegetable oil, and such ‘biofuels’ are not (4) ………… in the sport yet. It has to be mixed with normal fuel so that all parts of the car keep working.
Carrots and other root vegetables were used to make some parts inside and outside the car. Even the mirrors are made from potatoes! The sides of the car (5) ………… a mixture of natural materials from plants as well as other recycled materials.
The project is still young, so the scientists have not yet found out how ‘green’ the car is. They are planning many experiments to compare its (6) ………… against that of normal racing cars.