，，且，則銳角為

A． B． C． D．

D

解析試題分析：根據(jù)題意，由于，，且，那么則有，由于角為銳角，那么可知銳角=，故選D.
考點(diǎn)：向量的共線
點(diǎn)評(píng)：主要是考查了向量的共線的概念的運(yùn)用，屬于基礎(chǔ)題。

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