Digital SAT Reading and Writing Practice Question #555

In protoplanetary disks, the 'snow line' represents the distance from a young star where temperatures drop sufficiently for volatile compounds, such as water, to condense into solid ice grains. According to core accretion theory, the formation of gas giants requires these abundant ice grains to rapidly build a planetary core massive enough—roughly ten Earth masses—to gravitationally capture a thick atmosphere of hydrogen and helium gas. Conversely, inner rocky planets form where it is too hot for ice, relying solely on scarcer heavy elements. Yet, astronomers frequently discover 'Hot Jupiters'—massive gas giants orbiting their host stars much closer than Mercury orbits the Sun, well inside the theoretical snow line. Which of the following is the most logical conclusion that can be drawn from the passage?