What factor can physically obstruct cable installation in a building?

The option indicating tight spaces and physical barriers as a factor that can physically obstruct cable installation in a building is correct because these conditions directly impede access and movement during the installation process. Installers often encounter scenarios where conduit, walls, furniture, or other structures limit the available space for cable runs. Such physical limitations can lead to challenges in properly routing and securing cables, making the installation process more time-consuming and complex.

Weather conditions, while important to consider, primarily affect installation in outdoor settings rather than within the confines of a building. Available manpower, although influencing the pace and efficiency of the installation, does not inherently create a physical obstruction. Color code requirements are essential for ensuring that the cabling adheres to industry standards, but they do not relate to the physical ability to install the cables. Therefore, tight spaces and physical barriers stand out as the most relevant obstacle in this context.