Oil shale and tar sand as energy sources have some disadvantages.What is not one of these?

Question

Quizplus · Accepted Answer

Oil shale and tar sands have large potential supplies, not low. They are considered unconventional sources of fossil fuel with vast reserves, particularly in regions like the United States and Canada. The main concerns with their exploitation are environmental and efficiency-related, not scarcity of the resource itself.

Oil Shale and Tar Sand as Energy Sources Have Some