The correct answer is C. Gangubai Hangal.
Gangubai Hangal (1912-2009) was an Indian Hindustani classical vocalist from Karnataka. She was one of the most celebrated vocalists of her time and is considered to be one of the greatest female vocalists in the history of Indian classical music. She was known for her powerful voice and her mastery of the Kirana style of singing.
M.S. Subbulakshmi (1916-2004) was an Indian classical singer who was known for her versatility and her ability to sing in a variety of styles. She was also a noted actress and social activist.
Bhimsen Joshi (1922-2011) was an Indian Hindustani classical vocalist who was known for his powerful voice and his mastery of the Gwalior style of singing. He was one of the most celebrated vocalists of his time and is considered to be one of the greatest male vocalists in the history of Indian classical music.
Pandit Ravi Shankar (1920-2012) was an Indian sitar player and composer who was known for his mastery of the instrument and his ability to blend Indian classical music with Western music. He was one of the most influential musicians of his time and is considered to be one of the greatest sitar players in the history of Indian classical music.