Read the followingpassage 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.

Most people think of computers as very modern inventions, products of our new technological age.But actually the idea for a computer was (21)_______ out over two centuries ago by a man called Charles Babbage.

Babbage was born in 1791 and grew up to be a brilliant mathematician.He drew up plans for several calculating machines (22)_______ he called “engines”.But despite the fact that he started building some of these he never finished any of them.Over the years people have argued (23)_______ his machines would ever work.Recently, however, the Science Museum in London has finished building an engine based on one of Babbage’s designs.

It has (24)______ six years to complete and more than four thousand parts have been specially made.Whether it works or not, the machine will be on show at a special exhibition in the Science Museum to (25)_______ people of Babbage’s work.

But actually the idea for a computer was (21)_______ out over two centuries