Sand is supplied to the California coastal region primarily by:
• (a)Coastal erosion •
• (b)Local biological activity •
• (c)Rivers that flow from the Sierra-Nevada mountains
•(d)Ocean floor upwelling
I think the correct answer would be A. Sand is supplied to the California coastal region primarily by coastal erosion. It is a type of erosion that removes sand, sediments through the action of the waves, tidal currents or high winds in a certain beach system. The, the sands that had been eroded are moved to the coastal region of California.
