Concept:The verse “Iyyaka na budu wa iyyaka nasta‘in” belongs to Surah Al-Fatihah.Explanation:The phrase means “You alone we worship, and You alone we ask for help.”It appears in the opening chapter of the Qur’an, Surat Al-Fatihah, verse 5.Al-Fatihah is recited in every unit of the Muslim prayer.Therefore, among the given options, Surah Al-Fatihah is the correct source.Answer:C. Fathihah