Which of the following is a negative externality of creating a hydroelectric dam on a major river?

A. Lakes for tourists

B. Energy creation

C. Improved flood control

D. Environmental impact

The one that regarded as a negative externality of creating a hydroelectric dam on a major river is: D. Environmental impact

Installing Hydroelectric dam in the major river will change the chemical composition of the ecosystem in that area.

This will heavily affect the biodiversity in that ecosystem

I agree it's D, I got it right