38. Which was that Surah of the Qur'an which the Prophet Muhammed (Sallallahu Alaihi Wasallam) had recited when one of his enemies Utba after listening to it fell in Sajda (prostation)?

QUESTION-  Which was that Surah of the Qur'an which the Prophet Muhammed (Sallallahu Alaihi Wasallam) had recited when one of his enemies Utba after listening to it fell in Sajda (prostation)?

ANSWER-  The first five Ayaaths of Ham-Meem-Sajda