Question

health in panama improved as a result of construction of the panama canal because doctors protected laborers by
working to eliminate tropical diseases.
demanding medical education be available.
insisting on more healthcare funding.
working to improve drinking water.

Explanation:

During the Panama Canal construction, doctors focused on eliminating tropical diseases (like malaria and yellow fever) which were rampant. This directly protected laborers and improved health. Other options (medical education, healthcare funding, drinking water improvement) were not the primary focus of doctors' efforts for laborer protection during this context.

Answer:

A. working to eliminate tropical diseases.