A、Blood pressure, body weight and lifestyles. B、Blood levels, blood pressure and lifestyles. C、Blood pressure, age and lifestyle

New research from Australia shows that pets are good for your health. The findings of this new study suggest that people who have pets are at less risk from heart disease than those who do not.
    The new research was carried out over three years and examined 3,000 people. They took tests that measured a variety of different factors known to be involved in heart disease — blood pressure and blood levels. Also, people were asked about their lifestyles. The 800 people who owned pets had low levels on each of the factors measured than those who did not own pets. The study also showed that it did not matter what kind of pet was owned — a cat was as good as a dog —so the benefits could not be attributed to the exercises involved in walking a dog.
    The question is just how pets manage to make their owners more healthy. The obvious answer is that they make their owners feel more relaxed and happy. The Australian scientists who organized this study commented that if a new drug was available that was as effective as simply having a pet, then this drug would undoubtedly be considered a breakthrough in the control of heart disease.
Questions 33 to 35 are based on the passage you have just heard.
33. What is the relationship between one’s health and having pets?
34. What factors are measured in the research?
35. What does the research show?