What has been a long-term effect of the panama canal?

it has largely decreased the us military presence in latin america

it has greatly improved the amount of fertile farmland in nearby areas.

it has become one of the most important trade routes in the world.

it has quickened the spread of diseases like malaria and yellow fever.

I'm pretty sure that it's the spread of many diseases

The correct answer is D) it has quickened the spread of diseases like malaria and yellow fever.

A long-term effect of the Panama Canal is that it has quickened the spread of diseases like malaria and yellow fever.

Without a doubt, the Panama Canal has brought many benefits to international trade. It dramatically reduced the travel time for big cargo ships that before the canal had to go further down the tip of the South America Continent to continue their trips. However, on the side of the negative consequences, is the impressive number of mosquitos in the canal area due to climate conditions. Mosquitos increase the risk of spreading diseases like malaria and yellow fever.

what are local authorities doing to fix the problem

explanation:

one of the negative side effects were the economic losses the events of september 11th caused. many, many people lost their jobs as a result of a downturn in the economy after the terrorist attacks.