Don't leave matches or cigarettes on the table within ________ of little children．

A.hand

B.reach

C.space

D.distance

答案及解析： B

解析：

within reach of sb．相当于within sb．'s reach，意为“在(某人的)手能及之处；在力量所及的范围”．其反义短语是out of sb．'s reach，意为“在(某人的)手所不能及之处”．