Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions front 43 to 50.

   Homeopathy, the alternative therapy created in 1796 by Samuel Hahnemann, and now widely used all over the world, is based on the belief that the body can be stimulated to heal itself. A central principle of the “treatment” is that “like cures like”, meaning a substance that causes certain symptoms can also help to remove those symptoms. Medicines used in homeopathy are created by heavily diluting in water the substance in question and subsequently shaking the liquid vigorously. They can then be made into tablets and pills. Practitioners believe that the more a substance is diluted in this way, the greater its power to treat symptoms.

   However, in a new study, a working committee of medical experts at Australia’s National Health and Medical Research Council (NHMRC) has claimed that homeopathic medicines are only as effective as placebos at treating illness. Their research, involving the analysis of numerous reports from homeopathy interest groups and the public, concluded that there is no reliable evidence that homeopathy works. Moreover, researchers uncovered no fewer than 68 ailments that homeopathic remedies had failed to treat, including asthma, sleep disturbances, cold and flu, and arthritis.

   As a result of the findings, the NHMRC is urging health workers to inform their patients to be wary of anecdotal evidence that appears to support the effectiveness of homeopathic medicine. “It isn’t possible to tell whether a health treatment is effective or not simply by considering the experience of one individual or the beliefs of a health practitioner” says the report. Experts believe that most illnesses said to have been cured by homeopathy would be cured by the body on its own without taking the medicine. Apparently, many illnesses are short-lived by their very nature which often leads to people believing that it is the homeopathy that cures them.

            A more serious matter is highlighted by Professor John Dwyer of the University of New South Wales. As an immunologist, he is concerned about homeopathic vaccinations on offer for diseases such as HIV, tuberculosis, and malaria, none of which he considers effective. According to Professor John Dwyer, the concept that homeopathic vaccinations are just as good as traditional vaccinations is delusion, and those who believe it are failing to protect themselves and their children.

Question 45. What does the word “their” in paragraph 2 refer to?