Hot Jupiters Were a Surprise to Astronomers

Hot Jupiters were a surprise to astronomers. What is the current explanation for their existence?

A) Jupiters form as a companion to the host star, but fail to become actual stars themselves because they are not massive enough.
B) Jupiters are supposed to form far away from their host star, then they migrate closer through gravitational interactions with the protoplanetary disk.
C) The temperature of the hot Jupiters is highly uncertain, so they might not be as hot as the astronomers say.
D) Jupiters actually can form close to the host star, since they do not require as much hydrogen compounds and ice as originally thought.