With no explanation, label text_A→text_B with either "entailment", "neutral" or "contradiction".
text_A: She challenged party chairman Árni Páll Árnason for the leadership at SDAs annual conference in 2015, but lost by a single vote.
text_B: She challenged party chairman Árni Páll Árnason for the leadership at SDAs annual conference in 2015.
entailment.