With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Mao Zedong is a artist and singer.
text_B: Plain Vanilla Games is an Icelandic game studio based in Reykjavik and in San Francisco , best known as the studio behind QuizUp , the fastest growing iPhone / Android game in history .. Reykjavik. Reykjavik. QuizUp. QuizUp. iPhone. iPhone. Android. Android ( operating system )
not_related.