Explanation:

- M S Subbulakshmi: An iconic musician and a prominent figure in Indian classical music, celebrated for her divine voice and spirituality-infused performances.

- Option 1: Ghazal Music: Ghazals are poetic compositions usually set to music, focusing on themes of love and romance. Subbulakshmi was not primarily known for singing ghazals.

- Option 2: Hindustani Music: One of the two principal genres of Indian classical music, predominant in northern and central India. Subbulakshmi's main expertise was not in Hindustani music.

- Option 3: Sufi Devotional Music: This genre involves mystical themes, prevalent in Sufi traditions. Though spiritually rich, this was not Subbulakshmi's main genre.

- Option 4: Carnatic Music: Correct Answer. This is the classical music tradition of Southern India, and M S Subbulakshmi was renowned for her significant contributions to Carnatic music, earning her a legendary status.