Respuesta :
The correct answer is B. Seismometer, Seismometers are used to measure motion in the ground (seismic waves) created by earthquakes and volcanic activity. These machines allow seismotologist to map and measure these events.
B. Seismometer
A seismometer is an instrument that measures ground motions, such as caused by earthquakes, volcanic eruptions, and explosions. Records of seismic waves (seismograms) allow seismologists to locate and measure the size of events like these, and to map the Earth's internal structure.