The correct answer is C. Seismograph.
The seismograph is a term used to refer to a device created in 1842 by James David Forbes, which is used to measure seismic waves caused by telluric movements or earthquakes. It serves to know the amplitude of the waves and their propagation of the seismic movements produced by the tectonic plates. Due to this, the seismograph is the main tool used to detect, register and analyze earthquakes of any scale includes those humans cannot feel. So, the correct answer is C. Seismograph.
it sounds like either a or c