With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Bridget Moynahan went to Spain as an ambassador.
text_B: Excalibur BBS was a Windows-based GUI BBS Client  /  Server software , developed by Excalibur Communications .. Windows. Microsoft Windows. GUI. GUI. BBS. Bulletin board system. Client. Client ( computing ). Server. Server ( computing ). Excalibur was released in 1993 , and it has not been officially supported since 1999 , when Excalibur Communications ceased operations .
not_related.