Sustainable energy includes ___.

Sustainable energy includes ___.

• A. hydropower
• B. solar power
• C. wind power
• D. all of these

Answer: (D)

The main idea is that sustainable energy comes from sources that are renewable and environmentally friendly compared with fossil fuels. Hydropower, solar power, and wind power all fit this description because each relies on resources that are naturally replenished and they operate with little to no direct carbon emissions. Hydropower uses the energy of moving water, solar power uses sunlight through photovoltaic cells or solar thermal methods, and wind power converts the kinetic energy of wind into electricity. Because these sources draw on ongoing natural processes, they can be used repeatedly without depleting a finite supply, helping reduce greenhouse gas emissions over time. There are practical considerations—hydropower can impact aquatic ecosystems, and solar and wind are intermittent and may require storage or grid management—but these do not negate their sustainability. So, all of these are examples of sustainable energy.

The main idea is that sustainable energy comes from sources that are renewable and environmentally friendly compared with fossil fuels. Hydropower, solar power, and wind power all fit this description because each relies on resources that are naturally replenished and they operate with little to no direct carbon emissions. Hydropower uses the energy of moving water, solar power uses sunlight through photovoltaic cells or solar thermal methods, and wind power converts the kinetic energy of wind into electricity. Because these sources draw on ongoing natural processes, they can be used repeatedly without depleting a finite supply, helping reduce greenhouse gas emissions over time. There are practical considerations—hydropower can impact aquatic ecosystems, and solar and wind are intermittent and may require storage or grid management—but these do not negate their sustainability. So, all of these are examples of sustainable energy.