Earth’s surface is covered by more than 70% water, but scientists think that when Earth first formed it did not have any water. Which of the following could be a possible explanation for how the Earth obtained its liquid water? A. Impacts from meteorites and comets delivered water to Earth. B. Ice locked up in early Earth’s core slowly melted and was released. C. Atoms of oxygen and hydrogen combined during early Earth’s formation to produce water molecules. D. Water vapor from the atmosphere condensed and rained down on the planet creating the oceans over millions of years.

(me out over the last several centuries, scientists have made the following broad observations while investigating several branches of the life sciences: -the fossil record shows that different types of organisms have existed at different times in earth's history. -many organisms have similar body structures that seem to be adapted to different ways of living in their environment. -organisms of different species often share similarities in stages of embryonic development. -many species share genetic similarities, and almost all organisms use the same basic building blocks to construct proteins. -often, the extent of two species' similarities can be predicted from their geographic closeness to each other. -a great deal of change has been observed among species that have experienced strong selective pressures through many generations. scientists have carefully considered and rigorously tested the observations listed above. when scientists offer a of these observations, they are making 1.) testable explanation, deductive explanation 2.) scientific interference, scientific law