The correct options are
A The height of a waterfall in question
B Biodiversity and local residents
D Amount of water flowing per unit time
Hydroelectricity is a form of energy that harnesses the power of water in motion; such as water flowing over a waterfall. The length of the river does not play a factor, while the volume and speed of the flowing water does. Additionally, environmental concerns and the concerns of the locals must be taken into consideration.