If the Sun Were Traveling Around the Galactic Center Along

If the Sun were traveling around the galactic center along with companion stars (all in circular orbits) as depicted in Figure 13-17 of Comins,Discovering the Essential Universe,6th ed.,from which star would you measure a Doppler shift of their light? (Hint: Think about relative velocities and orbital velocities at different orbital distances from the galactic center.)

A) stars at the same orbital distance as the Sun
B) stars in directions 45° from the Sun's direction of motion
C) All the companion stars are moving along with the Sun and have no relative velocity with respect to it.
D) stars directly between the Sun and the galactic center