How does nuclear fission produce energy? a controlled nuclear chain reaction produces heat, driving steam turbines to produce energy. moving water turns turbines to produce electricity. carbon atoms are bombarded by small neutrons. an uncontrolled nuclear reaction produces heat, driving steam turbines to produce energy.

Option A, A controlled nuclear chain reaction produces heat, driving steam turbines to produce energy.

Explanation:

In a nuclear power plant,  the following processes takes place –

a)Series of nuclear chain fission reaction occur

b)Enormous amount of energy in the form of heat is released during each fission reaction

c)The condenser (heavy water) with in the plant absorbs this heat and converts into vapor.  

d)Water vapor or steam has high velocity which is then used to rotate the turbine connected with generator coil.  

e)Rotating coil  of generator produces electrical energy.

Hence, option A is correct