Question

Which statement describes the efforts required to complete construction of the Panama Canal?

The Canal Zone had to be secured against attacks by Panamanian rebel groups.
High wages had to be offered to workers recruited from many different countries in the region.
U.S. diplomats had to end decades of tension between Panama and its neighbors, Colombia and Costa Rica.
Immigrant laborers who had worked on the transcontinental railroad had to be shipped to Panama to provide engineering expertise.