The correct answer is (b), 30th October.
Sardar Vallabhbhai Patel was born on October 30, 1875. He was a prominent Indian lawyer and politician who played a leading role in the Indian independence movement. He is also known as the Iron Man of India for his role in uniting the princely states into the Indian Union.
Rashtriya Ekta Diwas, or National Unity Day, is a national holiday in India that is celebrated on October 30 to commemorate the birth anniversary of Sardar Vallabhbhai Patel. The day is observed to promote national unity and integration.
The other options are incorrect because they are not the birth date of Sardar Vallabhbhai Patel.