What Kind of Man Made Feature Would Likely Lead to Sand

Multiple Choice

What kind of man made feature would likely lead to sand loss on a beach regardless of active margin west coast North America. versus passive margin east and Gulf coast of North America. setting for the coastline?

A) building too close to sea- cliff and allowing urban runoff to seep into the rocks along the cliff
B) construction of offshore oil platforms
C) constructing a highway bridge over a bay mouth
D) dam construction