A、Because modern technology helped support the idea of the unconscious. B、Because a group of prominent psychologists decided to

W: Welcome to our TV show, Book Club. Today we are honored to have Professor David here to introduce his new book—The Unconscious Mind.
M: Thank you. The subtitle of my book is How Your Unconscious Mind Rules Your Behaviour. So you may have a clue about my book. By the way, have you read any books written by a psychologist?
W: When I was at college, I read Freud out of curiosity. I was deeply attracted by his ideas about the unconscious—a sort of shadowy basement of the mind that is inaccessible to rational thought, but which nevertheless influences people’s behaviour.
M: You are right. That is the core of Freud’s theory about the unconscious. Although it remained popular at dinner parties, the idea of the unconscious fell out of favor among 20th-century psychologists, thanks to the rise of more scientific approaches to psychology.
W: How about your latest book? Does it share similar ideas with modern psychology?
M: My book shows how the idea of the unconscious has become respectable again over the past couple of decades.
W: Why?
M: This development has been helped by experimental evidence of the effects of the subconscious and, especially, by real-time brain-scanning technology. It allows researchers to examine what is going on in their subjects’ heads.
W: It sounds quite convincing.
M: Yes. The experimental evidence suggests that, as Freud suspected, conscious reasoning makes up a small part of the activity in our brains, with most of the work taking place where we can’t tap into it.
W: So your book supports Freud’s theory completely.
M: Not 100％ though. Unlike Freud’s unconscious, the modern unconscious is a place of super-fast data processing, useful survival mechanisms and rules about the world that have been around by millions of years of evolution.
W: That is a new idea indeed.
M: The well-documented tendency of humans to categorize almost every piece of information they come across is a survival mechanism that evolved to aid quick decision making. This is the essence of my book.
Questions 5 to 8 are based on the conversation you have just heard.
5. Why did the woman read Freud when she was a college student?
6. Why was the idea of the unconscious popular again over the past years?
7. What can we learn from the experimental evidence?
8. According to the man, which is the key point of his book?