If an Astronomer Wants to Find the Distance to a Star

Multiple Choice

If an astronomer wants to find the distance to a star that is not variable and is located too far away for parallax measurements, she can:

A) use the star's light curve
B) find the star's luminosity class from its spectrum and read the luminosity from an H-R diagram
C) use Kepler's laws as modified by Newton
D) search for planets around the star since it is much easier to get the distance to planets
E) only throw up her hands in desperation; there is no way to even estimate the distance to such a star