The boy wrote last week．
A.a two-thousand-words articleB.two two-thousand-words articleC.a two-thousand-word articleD.two two-thousand-words articles在线课程C
解析：
由“数词+连字符+名词”构成的合成形容词，其中的名词必须用单数。此句若选 D，应将 words 后面的“s”去掉。