Which method uses light for measuring distances and angles?

Optical surveying is the method that utilizes light to measure distances and angles. This technique involves the use of various optical devices, such as theodolites and total stations, which depend on the principles of light to determine precise measurements. For instance, a total station emits a laser beam towards a target, and by measuring the time it takes for the light to return, it can calculate the distance to the object. Additionally, angles can be measured with high accuracy by aligning sighting lines with the aid of optical components.

In contrast, other methods mentioned may involve different principles. Reflective surveying often uses reflectors to bounce signals but relies more on electromagnetic waves than purely light. Electromagnetic surveying typically entails using a range of electromagnetic frequencies rather than solely light. Photographic surveying involves capturing images for analysis and mapping but does not center around direct light measurements in the way optical surveying does. Thus, optical surveying is uniquely characterized by its dependence on light for accurate distance and angle measurement, making it the correct answer.