What design feature allows water to run off a sloped roof effectively?

The correct answer centers around the function of eaves and gutters in facilitating effective water runoff from a sloped roof. Eaves are the edges of the roof that extend beyond the walls of the building, providing a channel for water to drip off and away from the structure. This design helps to prevent water from pooling at the base of the walls, which can lead to moisture damage and structural issues.

Gutters are attached to the eaves and collect the water that runs off the roof. They transport the water safely away from the foundation of the building, further ensuring that the property is protected from water damage. This combination of eaves and gutters is critical for managing rainwater and preventing it from causing deterioration to the building's structure.

While roofing shingles do play a role in waterproofing and protecting the roof surface, they alone do not direct the water away from the structure effectively. Overhangs and flashing are also important for protecting specific areas from water intrusion, but they do not carry away the water the same way eaves and gutters do. Ridges and valleys refer to the structural lines on a roof where two slopes meet, which can direct water flow but do not facilitate the runoff as efficiently as eaves and gutters.