Answer:
B. Liquid water flowed on its surface
The Grand Canyon is made of sedimentary rock that contains fossils up to 1 billion years old. and the several upper layers of rock contain terrestrial, or land-based, fossils, such as dragonfly wing impressions and the footprints of scorpions, centipedes, and reptiles
Act as a baseline to compare your data to
Megacity would probably have the biggest affect on the immediate environment and possible the outlands of the megacity as well.
