银杏属于裸子植物的原因是（ ）
A：种子外无果皮包被
B：植物体内有输导组织
C：种子外果皮较薄
D：受精过程脱离了水的限制
选词填空。
A. This is Mary. She's nine. She's tall. She's thin.
B. This is Danny. He's six. He's short. He's fat.
C. This is Eddie. He's nine. He's short. He's thin.
下列说法中正确的是( )
