In 2005, significant thawing of permafrost-lands that are frozen year-round—was reported in Alaska and Siberia. In Siberia, this
permafrost includes peat bogs that have trapped huge amounts of methane and carbon dioxide. Both of these are greenhouse
gases that trap heat from the Sun inside the Earth's atmosphere. As the permafrost thaws, it releases more greenhouse gases into
the atmosphere.
Why would it be difficult to limit the impact of thawing permafrost on global warming?
A. because the warmer the climate gets, the faster these greenhouse gases will escape
B. because farmers depend on peat moss to act as mulch and fertilizer in their fields
because it would cost companies a lot of money to switch to mordenvironmentally-friendly methods of producing peat
D. because the people who live in Siberia and Alaska would have trouble surviving the colder temperatures