According to a recent research, the old are more than twice as likely to have a positive attitude to life ______ the young.

【正确答案】 A

【答案解析】 句意为“根据最新的调查显示，老年人积极对待生活的可能性是年轻人的两倍多”。本题的倍数表达方式为“倍数+as...as...”。故选A。