Which of the Following Would Most Directly Favor the Core

Multiple Choice

Which of the following would most directly favor the core accretion model over the hydrodynamic instability model for the formation of giant planets?

A) an accurate census of the "hot Jupiters"
B) observations of comet-gas giant collisions in our Solar System
C) a detection of a massive, rocky core in the outer part of a very young protoplanetary disk
D) precise calculations of the formation sites of Jupiter and Saturn