Nuclear power plants are located all over the world. Nuclear power plants operate with low noise and the electricity generated is relatively cheap. Normally operating nuclear power plants will not pollute the environment. Therefore, nuclear power plants will not cause any harm. If the above statement is correct, which of the following questions the most serious of the above conclusions? ? ['Once a nuclear leak occurs, it will cause serious nuclear pollution to the local environment.', 'Construction of nuclear power plant will cause a certain degree of psychological panic to the local residents.', 'Nuclear waste generated by nuclear power plants will release high-energy particles and rays that are extremely harmful to living organisms, and their harmfulness will not disappear for a long time.', 'The process of developing nuclear power is extremely complicated, and successful development and safety maintenance require a high price from the government.']