During an excavation project, what instrument is commonly used to measure angles?

The theodolite is a precision instrument widely used in surveying and construction for measuring horizontal and vertical angles. Its design allows for accurate angle measurements critical during excavation projects to ensure proper alignment and positioning of structures. The theodolite can measure angles with very high precision, enabling surveyors and engineers to accurately set out boundaries and determine slopes or grades necessary for excavation.

While the other instruments listed have specific functions, they do not measure angles in the same precise manner. For instance, a laser level is focused on providing a consistent level reference across a distance, primarily used for leveling purposes rather than measuring angles. A plumb bob is used to determine verticality and is effective for checks on vertical alignment but does not measure angles at all. A survey pole aids in elevation readings and is generally used in conjunction with other instruments, but it is not employed directly to measure angles. Therefore, the theodolite stands out as the appropriate tool for angle measurement in excavation projects.