The aggregates required for one kilometer length of water bound macadam road per meter width and for 10 mm thickness is A. 8 cubic meter B. 10 cubic meter C. 12 cubic meter D. 15 cubic meter

The correct answer is B. 10 cubic meter.

The aggregates required for one kilometer length of water bound macadam road per meter width and for 10 mm thickness is 10 cubic meter. This is calculated by multiplying the length of the road (1 km) by the width of the road (1 m) by the thickness of the road (10 mm) and then dividing by 1000 to convert from millimeters to meters. This gives us 10 cubic meters.

Option A is incorrect because it is too low. Option C is incorrect because it is too high. Option D is incorrect because it is not a valid option.