Where is Angel Falls

A．Many people go to see Angel Falls every year.
B．Angel Falls looks like a silver thread from the distance.
C．Angel Falls is the highest waterfall in the world.
D．Angel Falls is a very impressive sight you would never forget.

A．A scientist named it Angel Falls.
B．It's named after an American pilot who first discovered it.
C．An American expedition named it Angel Falls.
D．No one knows.