Which offers a greater reward: a single obligatory prayer or twenty-four rak'ahs of Tarawih prayer, and does the reward for the obligatory prayer remain greater even with the large number of rak'ahs in Tarawih and the difficulty of performing them?

The obligatory duties (Fara'id) are the best means by which a servant can draw near to Allah, due to Allah Almighty's saying in the Hadith (definition) Qudsi: "My servant does not draw near to Me with anything more beloved to Me than what I have made obligatory upon him." The reward for an obligatory act is greater than the reward for a supererogatory act, and its recompense exceeds that of a supererogatory act by seventy degrees. Thus, the obligatory duties are more perfect and more beloved to Allah Almighty. Therefore, the reward for a single obligatory prayer is greater than twenty-four supererogatory rak'ahs.