种子植物比蕨类更适应陆地生活的重要原因是[ ]
A.有发达的机械组织和疏导组织
B.能产生种子
C.幼根生长快
D.发达的根茎叶
答案:B
is known to us all is that the 2012 Olympic Games will take place in London.
A.It
B.What
C.As
D.Which
若没某容量为8K字节的RAM起始地址为2000H,则其终止地址为( )。
A.21FFH
B.23FFH
C.27FFH
D.3FFFH