Which Curve Best Describes the Relationship Between Attitude Similarity and Attraction

Which curve best describes the relationship between attitude similarity and attraction?

A) A flat line suggesting no real relationship between the two
B) A straight upward-sloping line suggesting that as similarity increases, attraction increases
C) A curve that initially goes up, showing that up to a point similarity enhances liking, but then becomes flat
D) A curve that goes up but then turns down a bit showing that at very high levels of similarity, liking decreases