The term "rough in" refers specifically to the installation of the essential systems within a building, such as mechanical, electrical, and plumbing systems. This process typically involves placing the pipes, wiring, and ducts into their designated locations throughout the home, which is done before the walls are closed up and finishes are applied. This phase ensures that all of the necessary infrastructure is correctly positioned and ready for use but does not involve making any final connections, which would occur later in the construction process when the systems are ready for activation.
The other options describe stages of construction but don't capture the essence of "rough in." Foundations and structural framing are essential components of building construction, but they focus on the physical structure rather than the installation of utilities. Installation of roof decking and sheathing relates to the building's exterior rather than the critical internal systems being 'roughed in'. Overall, the correct definition encapsulates the preparatory work necessary for the mechanical, electrical, and plumbing systems essential for any building's functionality.