正确答案: B

马尾松和红松

题目：具二型叶。

解析：B

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举一反三的答案和解析：

[单选题]的孢子叶球均为单性同株。

松科植物

[单选题]黄瓜茎幼时柔软，不能直立，属于缠绕茎。( )

错误

[单选题]What does the writer dislike most about dinner parties in New Yorkers

The bill is not fairly shared.

[单选题]Not until I came home last night ________ to bed.

did Mum go

[单选题]

entire

[多选题].有关DNA分子结构的叙述，正确的是

DNA分子由4种脱氧核苷酸组成

磷酸与脱核糖交替连接构成DNA 链的基本骨架

解析：DNA双链上相对应的碱基以氢键连接，单链上相邻碱基之间通过脱氧核糖和磷酸二酯键联系起来，脱氧核糖和磷酸交替排列在外侧，构成DNA 链的基本骨架。碱基排列在内侧，与脱氧核糖直接相连

[单选题]It was a nice house, but _______ too small for a family of live.

rather

[单选题]同禾本科植物一样，姜科植物叶也有叶鞘和叶舌。( )

正确

[单选题]Doctors say that exercise is important for health, but it _______ be regular exercise.

must