With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Dysphonia can be characterized by breathy or harsh vocal qualities.
text_B: SP-473 is a state highway in the state of Sao Paulo in Brazil .. state highway. List of state highways in Sao Paulo. state. States of Brazil. Sao Paulo. Sao Paulo ( state ). Brazil. Brazil. Category  : Highways in Sao Paulo -LRB- state -RRB-. state. States of Brazil. Sao Paulo. Sao Paulo ( state ). pt  : SP-473
not_related.