You are leading a team exploring another planet. In your explorations you run an experiment. On one side of the planet you set up a
seismographic station. On the other side of the planet your colleagues detonate a large explosive device. At some time after the explosion, your seismograph records both a P-Wave, and an S-Wave. From these data you may conclude that:
a. The planet has an iron-nickel core.
b. The planet has a layer of molten material in its interior.
c. The planet has a solid interior.
d. The planet is tectonically active.