The answer is B. A guitar generally produces sound waves that propagate when the strings are strummed. The strings are displaced through the vibrations caused by contact of the hand and the guitar. You will also notice the vibrations by looking closely to the string. Wave particles continuously collide with each other to make a sustaining or prolonging sound.
Ice melts when heat energy causes the molecules to move faster, breaking the hydrogen bonds between molecules to form liquid water.
Because they believed that heavenly bodies’ circular motions where caused by their being attached to unseen resolving solid spheres
