Extracting oil from shale deposits a has been initiated on a large scale in the United States and will soon surpass Canada's production. b involves removing and refining waxy hydrocarbons called kerogen. c in the United States will take place mostly in northeast states as well as in Georgia and Florida. d in the United States has been studied by the EPA and found not to endanger ground water supplies.

The correct answer is;

b involves removing and refining waxy hydrocarbons called kerogen

Explanation:

Shale oil deposits are present in the United States in the Green River formation in Wyoming, Utah and Colorado and in the Devonian Oil  shales in Kentucky, Tennessee, Ohio and Indiana.

Shale oil has boosted crude oil production since 2014 and the United states  is presently one of the world's largest producers crude-oil.

Kerogen, found in oil shale is treated to produce shale oil with about 6.05 trillion barrels of oil in place globally.