Motilal Nehru, an Indian politician, is known for his opposition to the Public Safety Bill, 1928. He criticized the bill and referred to it as a direct attack on Indian nationalism and the Indian National Congress. He labeled it as the "Slavery of India, Bill No. 1."

Option 2, Lala Lajpat Rai, was also a prominent Indian freedom fighter and politician. However, there is no evidence to suggest that he opposed the Public Safety Bill, 1928, or made the specific remarks mentioned in the question.

Option 3, T Prakasam, was an important leader in the Indian National Congress and a supporter of the Indian independence movement. However, there is no record of him making the mentioned statement against the Public Safety Bill, 1928.

Option 4, Diwan Chaman Lai, was a lawyer and politician. There is no information available to suggest that he had any stance or made comments on the Public Safety Bill, 1928.

Hence, the correct answer is Motilal Nehru, as he was the one who voiced opposition to the bill and referred to it as a direct attack on Indian nationalism and the Indian National Congress.