Correct choice is (b) Piero Ginori Conti
The explanation is: In 1904, Italian scientist Piero Ginori Conti invented the first geothermal electric power plant in which steam was used to generate the power. On 4 July 1904, at Larderello, Piero Ginori Conti powered five bulbs from a dynamo driven by a reciprocating steam engine using geothermal energy.