If you look at the stars at night,
    A ) you see that all stars appear to have the same brightness
    B) you see that stars come in different brightnesses, but only because they are at different distances
    C) you see that stars come in different brightnesses, because they all have different intrinsic brightnesses, even though they are all at the same distance
    D) you see that stars come in different brightnesses, both because stars come in different intrinsic brightnesses and because they are at different distances

When called for, hold up the letter of your choice.