The key answer of exercise 1

a)

1. B
2. A
3. B
4. A
5. B
6. A

b)

1. He is popular because he is a hero who impresses us with the ways he solves crimes and mysteries.
2. He understood that trace evidence was very important and he used a lot of other methods of gathering evidence that modern forensic scientists use today such as handwriting analysis and fingerprints.