Read the following passage and mark the letter A, B, C, or D to indicate the correct answer to each of the questions…

Read the following passage and mark the letter A, B, C, or D to indicate the correct answer to each of the questions from.

[I] Fifty or sixty years ago, computers were very simple machines, but even then scientists believed that one day machines would be able to 'think' and that they would probably be as intelligent as humans. [II] Alan Turing, who had helped to break the German Enigma code during the Second World War, came up with an answer. [III] In a Turing test, judges sit at a screen and have a chatroom conversation with the chatbot programme. They don't know if they are chatting with another person or with a chatbot. After exchanging messages for five minutes, the judge decides if he or she is chatting with a human or a machine. [IV]

An American called Hugh Loebner was fascinated by Turing's idea, and in the early 1990s he offered a prize of $100,000 to the creator of the first chatbot to pass the Turing test. In order to win the $100,000, a chatbot must convince at least 30% of the judges that it is human. Many chatbots have entered the competition, but so far no chatbot has won the big money prize. Mitsuku, however, came very close.

In the conversation at the beginning of this article, Mitsuku is A and the real human is B. You can tell that A is not human because at one point in the conversation, A says ‘Humans are not too intelligent at times’.

Although Mitsuku failed to win the $100,000, it certainly won't be long before a chatbot is able to fool the Loebner judges into thinking that it is a real person.

But is the Turing test a good way to decide if a machine is intelligent? Critics argue that the chatbots in the competition are merely imitating humans. Humans are the only animals on Earth that can speak, and that's why Turing chose to focus on it. But what is really impressive, critics say, is machines that do things that we can't do. For example, it is amazing that Google can search hundreds of millions of websites for a single word in a matter of seconds, or that a NASA computer can control a rocket on a journey from Earth to Jupiter.

Fans of the Turing test, on the other hand, feel that humans are themselves machines. It's just that our brains are far more complex than computers. As philosopher and scientist Daniel Dennett said in a recent interview, ‘It's not impossible to have a conscious robot. You're looking at one.’

The word they in paragraph 1 refers to __________.