For a simple harmonic motion energy is given with:

Where k is a constant that depends on the type of the wave you are looking at and A is amplitude.
Let's calculate the energy of the wave using two different amplitudes given in the problem:

We can see that energy associated with the wave is 4 times smaller when we decrease its amplitude by half. So the answer should be C.
I am not completely sure, but I believe that it depends on the total mass of the Protons and Neutrons
I think the correct answer from the choices listed above is the second option. The relationship between the direction of energy and wave motion in a transverse wave would be the <span>energy direction is perpendicular to the motion of the wave. Hope this answers the question. Have a nice day.</span>