I think your sister is old enough to know（ ）to spend all her mon

I think your sister is old enough to know（ ）to spend all her money on fancy goods.
A、better than
B、than
C、other than
D、rather than
【正确答案】：A
【题目解析】：句意：我认为你妹妹年纪大了，不至于把钱都花在买奢侈品上。know better than to还没笨到；还不至于。