Correct Option (A):
Dr. B.R. Ambedkar was elected to the Constituent Assembly from West Bengal. Initially, he contested from the Bombay Presidency but was unsuccessful as the Congress-dominated provincial assembly did not support his nomination. Recognizing his invaluable expertise in constitutional law, the Indian National Congress leadership facilitated his election from West Bengal in 1946, where a Congress member vacated his seat for him. This enabled him to play a pivotal role in drafting the Indian Constitution, notably as the Chairman of the Drafting Committee.
Incorrect Options:
Bombay Presidency: Dr. B.R. Ambedkar was a resident of the Bombay Presidency and initially sought election from this region. However, he was not elected from here as the Congress-dominated provincial assembly did not support his nomination.
Madhya Bharat: This region was not involved in Dr. B.R. Ambedkar's election to the Constituent Assembly.
Punjab: Dr. B.R. Ambedkar was neither nominated nor elected from the province of Punjab for the Constituent Assembly.