Which one or more of the following statements apply to earthquake P waves? a. They are back-and-forth

Question:

Which one or more of the following statements apply to earthquake P waves?
a. They are back-and-forth vibrations like sound waves.
b. They are transverse vibrations like waves in a taut string.
c. They travel in straight lines through the earth’s interior.
d. They can pass through the earth’s core.