Concept:A latecomer who joins the congregation during the last sujud still completes the full prayer after the imam finishes.Explanation:When a devotee joins the congregational prayer in the last sujud, he is counted as having followed the imam for that final rak'ah.After the imam gives the salutation of peace, the devotee stands up and prays the rak'ahs he missed.This means he does not skip any part of the obligatory salat.He observes all the rak'ahs of the salat, even though he joined near the end.Answer:C. all the rak'ah of the salat.