Answer:
b) Dynamo
Step-by-step explanation:
A dynamo is an electrical generator that produces direct current with the use of a commutator. Dynamos were the first electrical generators capable of delivering power for industry, and the foundation upon which many other later electric-power conversion devices were based, including the electric motor, the alternating-current alternator, and the rotary converter.
Hence, The device which is used for converting mechanical energy into electrical energy is called Dynamo.
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