The key answer of exercise 2

a)

1. Without a doubt
2. firstly
3. Moreover
4. As a result
5. On the other hand
6. To begin with
7. Secondly
8. This is because
9. To conclude

b)

1. 3
2. 4
3. 2
4. 1

c)

• There are a number of advantages to animal testing. - Animal testing has some benefits.
• On the other hand, using animals in medical research has its drawbacks. - However, there are some disadvantages to animal testing.

d)

• The writer has used a rhetorical question.
• There is a saying, "The ends justify the means." Is this argument, enough, though, when it comes to animal testing in medical research?