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

My first piece of advice to people who want to start getting fit is: don’t buy an exercise bike. Typically, people who buy them use them for a week or so and then forget about them. They are effective if they are used regularly but you need to be determined. Most people will find it much easier to go for a gentle jog around the park.

As well as being easy to do, jogging is also relatively cheap compared to most other sports. You don’t need to buy expensive clothes if you’re just going running around the park or on the beach. The main thing is that they’re comfortable, and that they keep you warm in the winter and cool in the summer. There is one piece of equipment, however, that you will have to spend time and money on, and that’s your running shoes. Remember that you are not looking for a fashion item, but for something that will support your feet and protect you from injury. They can be expensive, but if they are good quality they will last you a long time. It's always best to get expert advice, and the best place for that is a sports shop.

As for the actual jogging, the secret is to start gently, and not to do too much at the beginning – especially if you haven’t had any exercise for a long time. Try a mixture of walking and running for ten minutes about three times a week at first. Once you are happy doing that you can then start to increase the amount you do gradually. After a few months you you should hope to be able to run at a reasonable speed for twenty minutes three or four times a week. It's important that you feel comfortable with whatever you do. If you do, you’ll start to enjoy it and will probably keep doing it. If it makes you feel uncomfortable, you’ll probably stop after a short time and return to your bad habits. In any case, training too hard is not very effective. Research has shown that somebody who exercises for twice as long or twice as hard as another person doesn’t automatically become twice as fit.

Which of the following would serve as the best title for the passage?

The word "They" in the passage refers to ____.