Answer:
B) The Precambrian Granite is the oldest because it is found on the bottom.
Step-by-step explanation:
Your oldest rock layer is going to be the one at the very bottom because as time goes on, the layers of the ground are going to pile on top of one another.
Process of Elimination:
A.: The Cambrian Shale is not the oldest; the Precambrian Granite is because it is at the very bottom. While it is true that it is older than the Carboniferous Limestone because it is below that, it is not the oldest one. Furthermore, the prefix "pre-" before the word "cambrian" suggests that it is even oldest than Cambrian Shale too.
B.: This choice literally restates what I wrote for A. This is why the Precambrian Granite is the oldest.
C. This is false because the oldest layer is found at the bottom, not the top.
D. This is false because the older ones are more toward the bottom and the newer ones more toward the top.
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