The correct answer is: A) S. Nijalingappa.
S. Nijalingappa was the Chief Minister of Karnataka from 1956 to 1960. He was the one who unified the three Kannada-speaking regions of Mysore, Hyderabad, and Bombay into the state of Karnataka.
B) Kengal Hanumanthaiah was the Chief Minister of Karnataka from 1962 to 1968. He was a strong advocate for the unification of Karnataka, but he was not the one who actually achieved it.
C) K.C. Reddy was the Chief Minister of Karnataka from 1972 to 1977. He was not involved in the unification of Karnataka.
D) Devaraj Urs was the Chief Minister of Karnataka from 1978 to 1980. He was not involved in the unification of Karnataka.
The unification of Karnataka was a long and complex process that took many years to complete. It was finally achieved in 1956, when the three Kannada-speaking regions of Mysore, Hyderabad, and Bombay were merged into the state of Karnataka. This was a major achievement for the people of Karnataka, and it has had a profound impact on the state’s history and development.