So desperate ________ that no one could help another, each ________ to save himself and his animals.[      ]

A. was the situation; was trying

B. the situation was; trying

C. the situation was; was trying

D. was the situation; trying

关于被子植物起源研究最有力的证据应是（）。

A.现代被子植物的地理分布

B.古植物化石

C.古代气候资料

D.古地理资料