Concept:The encounter between Bashirah and Muhammad (SAW) confirmed the signs of prophethood in the young Muhammad.Explanation:Bashirah was a Christian monk who met Muhammad (SAW) during a trading journey.He recognised in Muhammad the marks of a forthcoming prophet.This meeting was significant because it foretold and confirmed Muhammad's future使命 as a prophet of Allah.Thus, the encounter validated the prophethood that was later revealed to him.Answer:The encounter was important because it resealed (revealed) the prophethood in him — Option D.