单选题 New research suggests that speaking more than one language may delay different kinds of dementia, that is the lost of mental ability. In fact, researchers say, speaking two languages appears to be more important than the level of education in defending against dementias.
A study in India examined the effect of knowing more than one language in delaying the first signs of several disorders. Researchers studied nearly 650 people whose average age was 66. 240 of those studied suffered from Alzheimer"s, the most common form of mental decline. 391 of the subjects spoke two or more languages. Investigators found the dementias began about four-and-a-half years later in those who spoke two languages compared to those who spoke only one language.
Thomas Bak helped to organise the study. He is with the Center of Cognitive Aging at the University of Edinburgh in Scotland. He suggests that individuals who speak more than one language train their brains by moving back and forth between different words and expressions.
Mr. Bak believes this effort improves what scientists called executive functioning or attention to tasks, this mental ability often weakens in people with dementias.
Researchers found there was no extra gain in speaking more than two languages. They also did not see a delay in the first signs of Lewy bodies dementia, the disorder causes patients to see or experience things that do not real exist. They can also cause sufferers to move back and forth between being wide awake and really sleeping.
Mr. Bak says it does not appear important whether you learn a language at a young age or later in life.
"So it"s not something you sort of say that "you missed the boat when you do not do it as a baby". It is something that is still quite useful and powerful when you do it as an adult," he said.
Scientists found that speaking more than one language help delay the first signs of dementias, even in those who could not read.

【正确答案】 C

【答案解析】[解析] 事实细节题。本题考查我们能够从文章中获得的信息，注意抓住各个选项的关键词。根据C项中的Those who cannot read定位到原文最后一句。该句中指出，科学家发现，讲两种及两种以上语言能帮助延迟患上痴呆症状的时间，即使是对那些不识字的人来说也是如此。由此可知，即使是那些不识字的人，也能够通过会说不同的语言来推迟患上痴呆症的时间，C项表述正确，故选C。