This form of energy is collected and stored in photovoltaic cells.

• A. Hydropower
• B. Biomass
• C. Solar Energy
• D. Geothermal Energy

Answer: (C)

Solar energy is the form of energy collected by photovoltaic cells. Photovoltaic cells work by the photovoltaic effect: photons from sunlight excite electrons in a semiconductor, creating an electric current. The energy produced is electricity that can be stored in batteries or other storage systems; the cells themselves don’t permanently store energy. Other energy forms described rely on different natural sources: hydropower uses moving water to turn turbines, biomass stores chemical energy in organic matter and releases it through combustion, and geothermal energy comes from heat deep underground. So the energy captured by photovoltaic cells is solar energy.