67. Science can’t explain the power of pets ,but many studies have shown that the company of prts can help lower blood pressure ( 血压) and raise chances of recovering from a heart attack, reduce loneliness and spread all-round good cheer.Any owner will tell you how much joy a pet brings.For some, an animal provides more comfort than a husband/wife . A 2002 study by Karen Allen of the State University of New York measured stress(紧张) levels and blood pressure in people-half of them pet owners –while they performed 5 minutes of mental arithmetic(算术) or held a hand in ice water . Subjects completed the tasks alone , with a husband/wife, a close friend or with a pet . People with pets didit best. Those tested with their animal friends had smaller change in blood pressure and returned most quick to base line beart rates. With pets in the room, people also made fewer math mistakes that when doing in front of other companions. It seems people feel more relaxed (放松) around pets, says Allen, who thinks it may be because pets don’t judge.A study reported last fall suggests that having a pet dog not only raises your spirits but may also have an effect on your eating habits. Researchers at Northwestern Memorial Hospital spent a year studying 36 fat people and their equally fatdogs on diet-and-exercise programs; a separate group of 56 people without pets were put on a diet program. On average, people lost about 11 pounds, or 5% of their body weight. Dog owners didn’t lose any more weight than those without dogs but, say researchers, got more exercise overall-mostly with their dogs-and found it worth doing.What does the texomainly discuss?
(A) What pots bring to their owners.
(B) How pets help people calm down.
(C) People’s opinions of keeping pets.
(D) Pet’s value in medical research.