Please answer the following question: Read the article and select the best answer. Article: Researchers in the US say they might have discovered how to fight against and even _ some processes of ageing, at least in mice. Injecting the blood of young mice into the older ones improved their brainpower, a study found. Scientists at Stanford University plan to carry out trials in people in the hope that new treatments for dementia can be developed. "There are factors present in blood from young mice that can recharge an old mouse's brain so that it functions more like a younger one,"says Dr. Tony from Stanford University School of medicine. In the study published in Nature Medicine, mice aged 18 months were given injections of the blood taken from mice aged 3 months. The injected mice performed better on memory tests than mice of the same age that had not been given the blood. Dr. Tony said it was not known whether the same was true of humans, but a trial was planned. A research center in UK said the treatment restored certain aspects of learning and memory in mice, but was of unknown importance to humans. The research, while very interesting, did not test the type of brain damage that was seen in dementia, which is not a necessary consequence of ageing. Meanwhile, two similar studies by a separate team have thrown more light on how young blood may benefit the old, in mice at least. A substance in the blood of mice previously shown to have an anti-ageing effect on heart muscle also improved brain cells, according to a Harvard team. The research, published in Science, found the blood factors encouraged the growth of brain cells in old mice, and restored their sense of smell. The same chemical also improved muscle power of aged mice, the researchers found. Question: What's the author's attitude to the anti-ageing studies? Options: A: supportive B: objective C: negative D: doubtful
Answer:
B