Which roof slopes in one direction from the ridge line?

A roof that slopes in one direction from the ridge line is specifically known as a shed roof. This design is characterized by a single slope or plane, typically used in modern architecture or for structures like storage sheds. The straightforward design allows for efficient water runoff, making them practical in areas with significant rainfall. Additionally, they often provide the opportunity for higher ceilings on one side of the structure, enhancing the interior space.

In contrast, a hip roof consists of slopes in multiple directions, forming a peak without a vertical wall. A mansard roof, having a more complex design, includes two slopes on each side—a steep lower slope and a shallower upper slope. Decking is not a type of roof but rather refers to the process of laying boards or sheets to create a surface for the roof. The clarity of the shed roof's single-slope design is what sets it apart as the correct choice in this context.