Why Is There a Two Day Difference in the Sidereal

Multiple Choice

Why is there a two day difference in the sidereal and synodic months?

A) The Moon speeds up at perigee, and slows down at apogee.
B) The sidereal day is four minutes shorter than the solar day, and it adds up.
C) The Earth is closer to the Sun during the sidereal month.
D) The Earth is also revolving around the Sun, so the Moon must "catch up."
E) The Moslem lunar year is only 354 days long, on average.