What measurement tools are used to assess the motion and direction of tectonic plates on Earth?

The correct choice encompasses tools that are specifically designed to measure the precise movement of tectonic plates. GPS, or Global Positioning System, enables researchers to track the positions of points on the Earth's surface very accurately over time. This allows scientists to monitor the small movements of tectonic plates, which can occur at rates of just a few centimeters per year. The use of lasers in this context, particularly in conjunction with other techniques like laser ranging, can contribute to measuring distances with a high degree of precision, further enhancing the ability to observe tectonic plate motion.

In contrast, other tools listed, such as seismographs, are primarily used for detecting and recording seismic waves produced by earthquakes, which are a result of tectonic activity rather than measuring plate movements directly. Telescopes are unrelated to geology, focusing instead on astronomical observations. Similarly, magnetometers are used to measure the Earth's magnetic field and its changes, which can provide some information related to tectonic processes but do not directly assess plate movement. Lastly, thermometers and barometers measure temperature and atmospheric pressure, respectively, and have no relevance to the assessment of tectonic plate motion. This context illustrates why GPS and lasers are the best tools for measuring the movement of tectonic plates.