You are going to read part of an article about a famous inventor. For questions 15-17, choose the answer (A, B, C or D) which you think fits best according to the text.
Nikola Tesla was a multi-disciplinary genius whose inventions arguably make him the most significant inventor in history.
He was born around midnight, between July 9 and July 10, 1856 during a fierce lightning storm. According to family legend, midway through the birth, the midwife wrung her hands and declared the lightning a bad omen. “This child will be a child of darkness”, she said, to which his mother replied: “No. He will be a child of light.”
His discovery of the rotating magnetic field in 1882 led to a series of US Patents in 1888, which gave us the AC electric power system still in use today. This one achievement earned him the honour of being called “The Man Who Invented the 20th Century”.
His research went way beyond what has found its way into everyday use. He is the recognized inventor of the brushless AC induction motor, radio, remote control by radio, super-conductivity, fluorescent lighting, the bladeless turbine engine and pump, the capacitor discharge ignition system for automobile engines, the mechanical oscillator, and dozens of other inventions. He also discovered that useful energy could be extracted from the heat of the ambient air, and that electric power in the form of Radiant Energy could be broadcast to everyone in the world through the ground.
In his masterful article The Problem of Increasing Human Energy, first published in Century Illustrated Magazine in June 1900, Tesla discusses the “energy situation” like never before. After discussing every known method of gathering energy from the Natural World, Tesla departs into the unknown, writing about a machine that gathers heat from the ambient air. He calls it a “Self-acting Engine” since it could run indefinitely from the solar energy stored in the air. He calls it “the ideal way of obtaining motive power”.
Tesla worked for years trying to solve all of the technical issues presented by his idea. His work with liquefied air, his discovery of super-conductivity at ultra-low temperatures, his bladeless turbine and mechanical oscillator were all spin-offs from his work on the ambient air engine. He was convinced the system could work and that it was absolutely the best way to harness solar energy.
15. Tesla was called “The man who invented the 20th century’ because