Question

Which statement is true for particles of the medium of an earthquake P–wave?

Answer 1

I am pretty sure that the only statement which  is true for particles of the medium of an earthquake P-wave is being shown in the option : b)vibrate parallel to the wave, forming compressions and rarefactions. As you know,  it can be formed in two ways : from alternating compressions and rarefactions or primary wave. I bet you will agree with me.

Answer 2

The statement is true for particles of the medium of an earthquake P-wave is :
They vibrate in a direction parallel to that of the wave, forming compression and rarefaction
P-waves can be produced by earthquakes and recorded by seismographs.