Concept:Salatul Eidayn is the special congregational prayer offered during the two Islamic festivals.It has a fixed number of units that every Muslim should know for correct worship.Explanation:The Prophet Muhammad (peace be upon him) consistently performed the two Eid prayers as two units.Neither Eid al-Fitr nor Eid al-Adha is prayed with more than two raka'ah.The extra takbirat recited in the first and second units do not increase the total number of units.Scholars agree that the established Sunnah confirms two raka'ah for each Eid prayer.Examining the given options, the number that matches this practice is two.Answer:A. Two