What dual change did condensation of water vapour bring in Earth's evolution?

Correct answer: Rainfall occurred and hydrosphere began to form

The direct answer is Option C: rainfall occurred and the hydrosphere began to form. Condensation means that water vapour cooled and changed into tiny liquid-water droplets. As the early Earth became cooler, these droplets joined, fell as rain, and collected in low areas. This created the first lasting bodies of surface water, which is the beginning of the hydrosphere, the water part of Earth. Option A is wrong because cooling of the core and Moon formation were not the direct dual result of condensation. Option B is wrong because condensation did not melt the crust or create the Sun. Option C is correct because it gives both linked results: rainfall and accumulation of water. Option D is wrong because condensation did not end oxygen or life; these claims are unrelated. Memory cue: condensation means vapour becomes drops, so remember “rain first, hydrosphere next.”