Correct Option (b):
On 16th October 1905, the Partition of Bengal officially came into effect. This administrative division, enacted by Lord Curzon, the then Viceroy of India, aimed to separate the largely Muslim eastern areas from the largely Hindu western areas. While the British cited administrative efficiency, the move was widely perceived as an attempt to weaken nationalist sentiments and create a communal divide. The day was observed as a day of mourning, with widespread protests, fasting, and symbolic acts of unity like tying rakhis. This event served as a major catalyst for the Swadeshi Movement.
Incorrect Options:
Option (a): The formal proclamation of the Swadeshi Movement was made on 7th August 1905 at the Calcutta Town Hall, well before 16th October 1905. This proclamation called for the boycott of British goods as a protest against the impending partition.
Option (c): Dadabhai Naoroji declared 'Swaraj' (self-rule) as the goal of the Indian National Congress during its Calcutta Session in 1906, not on 16th October 1905.
Option (d): While Lokmanya Tilak was a significant leader and proponent of the Swadeshi Movement, particularly in regions like Poona and Bombay, the movement itself originated as a direct response to the Partition of Bengal. Its formal inception and widespread adoption were not solely initiated by Tilak in Poona on this specific date.