The tool that would be most useful to him would be a seismometer. It is an<span> instrument that measure motion of the ground, including those of seismic waves generated by earthquakes, volcanic eruptions. Hope this answers the question. Have a nice day. </span>
The answer is B. Mountains.
How does the Earth create a magnetic field?
The Earth’s magnetic field is created by the rotation of the Earth and Earth's core. It shields the Earth against harmful particles in space. The field is unstable and has changed often in the history of the Earth.