D). To show points of interest where visitors can go.
Explanation:
A road map is primarily employed as a communication/navigation tool that displays the links between the roads and transport.
As per the question, a state tourism office would use a road map in its brochures 'to show points of interest where visitors can go' as it would assist in promoting the tourism(by providing information about the links that would assist the visitors to navigate more conveniently) at a particular geographical location. Thus, <u>option D</u> is the correct answer.
Natural process by which water soluble substances (such as calcium, fertilizers, pesticides) are washed out from soil or wastes. These leached out chemicals (called leachites) cause pollution of surface and sub-surface water.
