Question

fossil fuels are formed from natural biological matter. why are they classified as a nonrenewable resource?
because they are too expensive to be considered a viable long-term resource.
because they take millions of years to form and cannot be replaced in a human lifetime.
because they are replenished by natural processes as quickly as they are used.
because they do not produce any greenhouse gases when burned.

Explanation:

To determine why fossil fuels are nonrenewable, we analyze each option:

• The yellow option is incorrect because cost doesn't define renewability.
• The purple option: Fossil fuels form over millions of years. Human lifetimes are too short to wait for their natural re - formation, so they can't be replaced in our time frame, which fits nonrenewable criteria.
• The orange option is incorrect as nonrenewable resources aren't replenished at the rate of use, but the key for fossil fuels is the extremely long formation time (not just the replenishment rate comparison).
• The teal option is wrong because fossil fuels do produce greenhouse gases when burned.

Answer:

B. Because they take millions of years to form and cannot be replaced in a human lifetime. (Here we assume the purple option is labeled as B for the multiple - choice context. If the original labels were different, adjust the label accordingly while keeping the text of the option.)