Answer:
The answer is D
Step-by-step explanation:
Nikola Tesla was a scientist, a discoverer and a physicist, a thinker in the old days that wanted to know what electricity was. Thomas Edison is known for his discovery in many fields such as motion, mass communication and so on.
The answer is D because the author includes Tesla’s opinion that Edison’s trial and error method of invention is as efficient as looking for a needle in a haystack.