It is possible but it is meaningless. If the speed reaches the rated speed, the power of 100W is first reduced by inputting the power loss of the motor into the generator and then discarding the power factor of the loss of the generator. In the end, the electricity generated is only about 60 or 70 watts. Do a generator experiment. If yes
A. Wind power generation, that is, generating electrical energy through the rotation of wind turbines, that is, converting mechanical energy into electrical energy, so this option is correct;
B. The motor works, that is, consumes electrical energy. Mechanical energy is generated, so it is a process of converting electrical energy into mechanical energy, which does not meet the meaning of the question;
C. A steam turbine is a rotary prime mover that uses steam to do work. The steam turbine converts the thermal energy of steam into Mechanical energy, therefore, is the conversion of internal energy into mechanical energy, which does not conform to the meaning of the question;
D. Solar battery charging converts solar energy into electrical energy, which does not conform to the meaning of the question.
So choose A.