a. The Earth's orbit around the moon is in the form of a slightly flattened circle and the sun is not at the center of the orbit, but it is lightly off to one side.
b. The Earth's orbit around the sun is flattened circle and the sun is at the center of the orbit.
c. The Earth's orbit around the sun is in the form of a slightly flattened circle and the sun is at the center of the orbit.
d. The Earth's orbit around the sun is in the form of a slightly flattened circle and the sun or of the orbit but it is lightly off to one side.
