According to the principle of superposition, layers A, B, and C are older than layer D, as they are below it in the stratigraphic sequence. ;
A and B is the correct answer lava is formed before crust
According to the principle of superposition, layers A, B, and C are all older than layer D, since they are located below it. Therefore, the correct choice is A, B, and C. This shows that all three layers preceded layer D in formation.
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