Of the three houses, the family prefers the more isolated one.

Of the three houses, the family prefers the more isolated one.
【正确答案】：more →most
【题目解析】：形容词的最高级前面要加the，而比较级没有the；比较级用于两者之间的比较，最高级用于三者或三者以上的比较，根据前面的three houses可知该用最高级。