I think it's D. I'm not positive though.
Answer: The Precambrian Era comprises all of geologic time prior to 600 million years ago.
Explanation: The Precambrian was originally defined as the era that existed before the emergence of life in the Cambrian Period. It is known that life on Earth began by the early Archean and that fossilized organisms became more and more abundant throughout Precambrian time.
Submarine Canyon
Submarine Canyon's are steep-sided valley canyons cut into the seabed of the continental slope.
Picture please ? So I can see how to answer this