Explanation:

- The Banking Regulations Act was enacted to regulate banking firms in India.

- Option 3: 1949 - The correct answer is 1949. The Banking Regulations Act was passed in this year, shaping India's banking sector by providing a framework for the regulation of banks.

- Option 1: 1947 - This was the year of India's independence, with many changes but not this act.

- Option 2: 1948 - This was a year of industrial policies and economic restructuring post-independence.

- Option 4: 1950 - The year the Indian Constitution was enacted, but unrelated to this act.

- Option 5: 1951 - Known for the first Five-Year Plan in India, not relevant to the Banking Regulations Act.