单选题 According to Fozard's argument, people can make their brain work more efficiently by______ .

A、 taking part in various mental activities
B、 making frequent adjustments
C、 going through specific training
D、 constantly doing memory work

【正确答案】 A

【答案解析】[解析] 细节判断题。短文第三段中，Most of us don't need that kind of skill．Such specific training is of less interest than being able to maintain mental alertness…they challenge brains with different mental skills．这几句话表明，从事各种脑力活动有助于保持脑子活力。