What effect did crust formation have on Earth's outer spheres?

Correct answer: It created a stable surface where water could remain and the hydrosphere could develop

The governing concept is the early evolution of Earth’s solid, liquid and gaseous spheres. As the young planet cooled, a solid crust formed around its hotter interior. This crust provided a relatively stable surface and depressions in which condensed water could collect instead of continually mixing with molten material. The accumulation of water helped the hydrosphere develop, while later interactions among the crust, atmosphere and oceans shaped Earth’s surface environment. Option B is correct because it expresses this sequence. Options A, C and D confuse Earth’s later crustal development with galaxy motion, the origin of the universe or the earlier formation of the Sun.