Batter boards are used to show the excavation and foundation crew where ________ .

Batter boards are critical in the construction process as they serve as reference points for the layout of a building. They are typically a set of wooden frameworks that are set up outside the intended foundation area. Their primary function is to provide a visual representation of where the exterior walls will be located, allowing the excavation and foundation crew to accurately position the foundation elements according to the architectural drawings.

Proper placement of the batter boards ensures that the lines of the building align with the design specifications, which is essential for achieving the correct structure. This helps avoid potential issues later in the construction process, such as misalignment or incorrect foundation placement.

The other options address elements that are important in construction but are not the primary role of batter boards. For instance, while windows, electrical outlets, and plumbing locations are vital to building plans, the initial focus during excavation and foundation work is primarily on the exterior walls, which define the building's overall footprint and dimensions.