Concept:A latecomer who misses two rak’ats in congregational Maghrib follows the imam in the remaining rak’ah and then completes what he missed by himself.
Explanation:He joins the imam in the third rak’ah and follows him until the imam says the taslīm.
After the imam’s taslīm, he gets up to make up the two missing rak’ats.
He prays the first of the two with Sūrah al-Fātiḥah and another sūrah, then sits for the first at-tashahhud.
He then stands and prays the next rak’ah with Sūrah al-Fātiḥah only.
After this, he sits for the last at-tashahhud and completes the prayer with taslīm.
So, in completing the missed part of the prayer, he makes two sittings for at-tashahhud.
Answer:C. two sittings.