Which of the following is not true about a nuclear power plant? they produce fewer carbon emissions than a coal-fired power plant. they are a relatively minor contributor to the usa's energy demands. they produce radioactive waste that must be safely stored for many years. they can explode like a nuclear bomb.

Nuclear power contributes a significant percentage of electricity in the USA. 20% of USA electricity generation is by nuclear power plants. This is the second biggest energy source in the United States after fossil fuels.  

The biggest challenges that are posed by nuclear energy is safety and radioactive waste. Nonetheless, nuclear power is among the cleanest energy sources on the planet in terms of emissions.