康采恩生产体系共分为（）个方法模块。
A.39
B.40
C.41
D.42
参考答案：C
—The sick old man can't find any place__ he can live.
—What a poor man, why not give him a hand? [ ]
A. which
B. in that
C. where
n个顶点的连通图中边的条数至少为______。
A．0
B．1
C．n-1
D．n
