Fossil fuels are source of electricity and heat for homes. Hydro-power is used to create large volume of electricity. Solar power use light reflection mirrors to trap the energy and convert into electricity. Bio energy is used as an alternative to traditional oil. Geothermal power is derived from the heat beneath earth's surface.
The correct answer is - B. Recession.
The recession can simple be defined as a decline in the Gross Domestic Product for at least two quarters/six months in a row in a certain country, or economic organization.
A recession has experienced every country in the world, and while some have been only on the short term, and have made quick recoveries, some have been having it much harder and for longer periods of times, which can even lead a country or economic organization to bankruptcy.
B. Revolution. I think?
(And sorry you had to wait a whole year!) :0