Children who are not active or diet is rich in fat will gain weight quickly.
A. what
B. whose
C. which
D. that
网友回答
A. what
(答案→)B. whose
C. which
D. that
解析：考查定语从句，先行词为Children，有两个定语从句，第一个为who are not active，第二个为whose diet is rich in fat will gain weight quickly. Whose作定语修饰diet，故选B。