下列检查中对缺铁性贫血最有诊断价值的是（）
A.血红蛋白减少
B.血清铁减少
C.红细胞呈小细胞低色素
D.骨髓铁染色阴性
E.总铁结合力增高
参考答案：D
( ) In sociolinguistics，speech community refers to a group of speakers who constitute a community and share the same language or a particular variety of language．Speakers of English in general might be treated as such a community.
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