The first National Professor of India was

Concept: The title ‘National Professor’ is India’s highest academic distinction, awarded by the Government of India to honour a scholar of outstanding eminence in a chosen field. Only a small number of scholars in history have held it, each recognised for a body of work that reshaped their discipline.

Application: This honour was first conferred on the physicist C. V. Raman, making him free India’s inaugural National Professor. Raman earned this recognition on the strength of his discovery of the scattering effect that bears his name — the change in wavelength of light scattered by a medium — for which he received the 1930 Nobel Prize in Physics, becoming the first Asian scientist to win a Nobel Prize in the sciences.

Cross-check — the other options:

• M. S. Krishnan was a geologist who later headed the Geological Survey of India; his recognition came from the earth sciences, a different discipline from the one for which Raman was honoured as National Professor.

• S. N. Bose is celebrated for the statistical method that, extended by Einstein, became Bose–Einstein statistics; he was himself appointed a National Professor years after Raman had already been the first to hold the title.

• S. K. Mitra is known for ionospheric radio research and received a National Professorship in a later round, after Raman had already been the first to hold the title.

Hence, among the options, C. V. Raman is the scientist who held the title of India’s first National Professor.