问题
They arrived at a farmhouse, ______. [ ]
A: in front sat a small boy
B: in front of it sat a small boy
C: in front of which a small boy sat
D: sitting in front of which was a small boy
B: in front of it sat a small boy
C: in front of which a small boy sat
D: sitting in front of which was a small boy
正确答案是：
