Write a multi-choice question for the following article, with the given choices and answer: Article: Looking for a new weight loss plan? Try living on the top of a mountain.Mountain air contains less oxygen than air at lower altitudes,so breathing it causes the heart to beat faster and the body to burn more energy. Studies have found that athletes training at high altitudes tend to lose weight.Doctor Florian Lippl in Germany wondered how the mountain air would affect _ individuals if they weren't doing any more physical activity than usual. Lippl and his colleagues invited 20 obese men to an environmental research station about 300 meters below the summit of Zugspitze, mountain around 2, meters near the Austrian border.2,970 This was no hiking expedition. They were allowed to eat as much as they liked. men also gave The blood so that researchers could test for hormones linked to appetite and obesity.At the end of the week, men, the whose weight starting out was 105 kilograms, had lost about 1.5 kg on average.The men's blood pressure also dropped,which the researchers owed to weight lost. Exactly what caused the weight loss is uncertain.Loss of appetite is common at higher altitudes, and indeed the men ate significantly less than usua!--about 700 calories fewer per day. Appetite loss at high altitudes could certainly be key,notes Damian Bailey,a physiologist, who himself recently lost 11 kg during a 3-month expedition to the Andes in Chile. Unfortunately,for the average person there's no treatment that can resemble living at high altitudes, says Lippl.He says,half-jokingly, obese people plan their holidays,they might not "If go to the sea,but maybe to the mountains." Options: A one's body weight B one's blood pressure C one's way of living D one's heart-beating rate Answer: A one's body weight Question:
Hormones were tested in the research because they could affect _ .