Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks from 19 to 24.

Most people think of computers as very modern (19) ______, products of our new technological age. But actually the idea for a computer had been worked out over two centuries ago by a man (20) _________ Charles Babbage. Babbage was born in 1791 and grew up to be a brilliant mathematician. He drew up plans for several calculating machines (21) ______ he called "engines". But despite the fact that he (22) ______ building some of these, he never finished any of them. Over the years people have argued whether his machines would ever work. Recently, however, the Science Museum in London has finished building (23) ______ engine based on one of Babbage's designs. (24) ______ has taken six years to complete and more than four thousand parts have been specially made.

Question 19