Which of these is a drawback of using natural gas?
a. it is fairly safe for use in homes.
b. it burns more cleanly than crude oil products.
c. scientists have developed new ways of extracting it.
d. during its extraction, groundwater can be contaminated.

D. During its extraction, groundwater can be contaminated.

Explanation:

The exploitation of natural gas can contaminate drinking water in rock layers. The statement is from a study published in the American Academy of Sciences magazine, "PNAS", according to which the technique used for gas extraction, hydraulic fracturing, facilitates the leakage of shale in a gaseous state and salt water to aquifers , contaminating them. Although they found no contamination in the nearby springs, the researchers found the presence of high levels of salinity, pointing to the risk of contamination.

With that, we can say that one of the disadvantages of natural gas is that its extraction can contaminate groundwater.

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