正确答案: A

具网纹、孔纹导管

题目：下列各种输导组织特征中，( )的性状最为进化．

解析：A

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举一反三的答案和解析：

[单选题]What documentation should a couple with a 7-year-old child carry when they drive a car from Canada to America?

Two vaild passport crads and a certified copy of a birth certificate.

[单选题]根据下面，回答 57 ~ 60 题： EIt's only 4 hours flying time from Sydney, but a world away. What better place to rest than a country where the only place people hurry is on the football field and things are done in "Fiji time"?

On the island of Viti Levu

[单选题]藻类植物都是单细胞或群体。( )

错误

[单选题]分子中含有某些不稳定基团，可发生水解的物质（ ）。

三者都是