The following passage discusses the historical development of the electric lightbulb.
For many years, the invention of the electric lightbulb was attributed solely to Thomas Edison in 1879. However, historical records indicate that many inventors had been working on similar technology for decades. For example, in 1802, Humphry Davy created the first electric light by passing a current through a platinum strip. Later, in 1840, Warren de la Rue developed an efficient bulb using a coiled platinum filament. Edison's true contribution was not the primary invention itself, but rather the development of a long-lasting, commercially viable filament and a complete electrical distribution system that made the lightbulb practical for mass use.
Part A: Which choice best states the central idea of the text?
Part B: Based on the text, what specific detail regarding the work of Humphry Davy and Warren de la Rue supports the claim that Edison was not the first to create electric light?