What Is Spectroscopic Parallax

Multiple Choice

What is spectroscopic parallax?

A) an apparent change in position of the absorption lines in a star's spectrum due to the Doppler shift caused by Earth's motion around the Sun
B) an apparent change in position of a nearby star compared with distant background stars due to the motion of Earth around the Sun
C) a change in position of the absorption lines in a star's spectrum due to the Doppler shift caused by the star's motion around the center of mass in a binary star system
D) the distance to a star measured using the spectral luminosity class of the star and the inverse square law