When Venus Is Seen at Inferior Conjunction, a Ring of Light

When Venus is seen at inferior conjunction, a ring of light is seen around it. What does this ring tell astronomers about Venus?

A) The Venusian atmosphere is so hot that it glows, even on its dark side.
B) Venus has auroral displays like those on Earth, which extend over the whole planet.
C) Venus is very massive because the gravitational field of Venus is sufficient to bend sunlight around the planet toward Earth.
D) Venus has a thick atmosphere that scatters sunlight toward Earth.