Question

what does a seismograph record?
a the location of the epicenter
b the forecast of an earthquake
c the ground movements caused by seismic waves
d the speed of seismic waves

Explanation:

A seismograph's core function is to detect and record the physical movement of the ground that is generated by seismic waves during an earthquake. The epicenter location is calculated using data from multiple seismographs, not directly recorded by one. Seismographs do not forecast earthquakes, and while seismic wave speed can be derived from their data, it is not the direct recorded output.

Answer:

c. The ground movements caused by seismic waves