梨锈菌的转主寄主为（）。
A.马尾松
B.柏属植物
C.十大功劳
D.小檗
参考答案：B
________, I think, and the problem could be settled．
A．A bit more effort
B．So long as you keep up your spirits
C．If you doubt your efforts
D．Making great efforts
七巧板(塑料制)
