Choose the correct word A, B, C or D for each gap to complete the following passage

Thomas Edison was one of the greatest (21)_________ of the world. He was responsible for more than one thousand inventions  including the electric light bulb and the record player. He also created the world"s first industrial research laboratory .
‎Edison was born in 1847 in Ohio, USA. (22)__________ he was 10 years old, he set up a small laboratory after he had read a science  book his mother showed him. In 1869, he (23)________ some money and began to make inventions. In 1876 he built a new laboratory so that he could spend all his time inventing . He planned (24)_______ out minor inventions every ten days and a ‘big trick" every six months. He developed many devices that brought great benefits  to people"s life. He once said that the value of an idea lay in the using of it. Edison died (25)________ 1931, after having a remarkably productive  life.

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