Option C: Dynamo converts mechanical energy into electrical energy. A dynamo consists of coils of wire rotating within a magnetic field. When the coils rotate, they cut through the magnetic field lines, inducing an electromotive force (EMF) according to Faraday’s law of electromagnetic induction. This EMF causes a flow of electrons, generating electrical current. In essence, the mechanical energy used to rotate the coils is converted into electrical energy. This process is commonly seen in devices like electric generators and bicycle dynamos, where mechanical motion, such as the rotation of a turbine or the movement of bicycle wheels, is harnessed to produce electricity. Option A (high voltage into low voltage) is incorrect, as dynamos typically produce electricity at a relatively low voltage, which can then be transformed to higher voltages using transformers. Option B (electrical energy into mechanical energy) is incorrect, as that describes the operation of an electric motor, not a dynamo. Option D (low voltage into high voltage) is incorrect because dynamos generate electricity rather than transforming voltage levels. Therefore, option C accurately describes the function of a dynamo in converting mechanical energy into electrical energy through electromagnetic induction.