Explanation:

- The Planning Commission of India was established on March 15, 1950.

- It was constituted by an executive decision of the Government of India.

- Its primary purpose was to create and implement five-year plans for the country's economic development.

- Option 1: 1955 is incorrect as it is five years after the actual establishment.

- Option 2: 1945 is incorrect as it predates India's independence.

- Option 3: 1960 is incorrect as it is a decade later than the actual year.

- Option 4: 1950 is the correct answer.