Concept:Eid al-Adha, the Festival of Sacrifice, marks the end of the Hajj pilgrimage.Explanation:The 9th of Dhul-Hijjah is the Day of Arafat.The following day is the 10th of Dhul-Hijjah.Eid al-Adha is observed on this day.This is when Muslims offer the ritual sacrifice.Answer:Option A. tenth.