1. What is the difference between primary waves (P-waves) and secondary waves (S-waves)? A. Primary waves are elastic waves that travel faster than secondary waves that are compression waves.

B. Primary waves are compression waves that travel faster than secondary wave with elastic rope-like movement.

C. Primary waves are compression waves that travel slower than the secondary wave with elastic rope-like movement.

D. Primary waves are rolling waves and secondary waves cause horizontal shifting, both move along the Earth's surface.