The correct option is D It is extremely useful for navigation.
The mercator projection is most widely used as it maintains the shape of the countries. This means the shape of the countries that you see in this projection is almost similar to what it looks like on a globe. Secondly, a mercator projection is extremely useful for navigation. It preserves the correct angle of the direction between two points. Mercator’s projection does not preserve lengths or areas further from the equator.