If a Dam Is Installed Across a River,what Effect Will

Multiple Choice

If a dam is installed across a river,what effect will this have on the coastline?

A) It will not allow any fish to swim down the river and into the ocean.
B) It will stop the flow of water,which will lower sea level.
C) It will change the chemistry of the water and pollute the estuary.
D) It will starve the coast of sediment,and the beaches will disappear.