Which was an obstacle in building the National (Cumberland) Road?

Responses

Roads had to be built by hand with picks and shovels.Roads had to be built by hand with picks and shovels.

The Spanish blockaded the Mississippi River.The Spanish blockaded the Mississippi River.

American Indians attacked the crews building the road.American Indians attacked the crews building the road.

Workers had to build a bridge over the Grand Canyon.

American Indians attacked the crews building the road.