Read this excerpt from "A Student's Guide to Global Climate Change." Climate change poses risks for cities near the ocean. Places like Miami; New York City, New Orleans, and Venice, Italy, could flood more often or more severely if sea level continues to rise. If that happens, many people will lose their homes and businesses.

What can people do about it?
Coastal cities can prepare for climate change by
protecting or restoring natural shoreline buffers like
sand dunes and wetlands, improving storm drainage
systems, and building protective barriers where
necessary

Based on the excerpt, what conclusion can be
drawn about protective barriers?

O They should be built along coastal communities.
O They should be built where natural barriers are
missing.
O They are the same as natural barriers.
O They are usually unnecessary along shorglines.