**Introduction:**
Bhagat Singh and B.K. Dutt were prominent figures in the Indian independence movement. On 8th April 1929, they threw a bomb in the Central Legislative Assembly in Delhi as a protest against the Public Safety Bill.

**Explanation:**
The Public Safety Bill, also known as the Trade Disputes Bill, was introduced in the Central Legislative Assembly by the British colonial government in India. The bill aimed to give the government sweeping powers to suppress any form of dissent or protest against British rule. It sought to curtail the rights of workers and restrict their ability to strike or organize labor unions. The bill was seen as a direct attack on the civil liberties and rights of the Indian people.

**Reasons for the Protest:**
1. Opposition to Repressive Laws: Bhagat Singh and B.K. Dutt were staunch opponents of repressive laws such as the Public Safety Bill. They believed that these laws were being used by the British government to suppress the voices of the Indian people and deny them their basic rights and freedoms.
2. Symbolic Protest: By throwing a bomb in the Central Legislative Assembly, Bhagat Singh and B.K. Dutt wanted to send a strong message to the British government and the Indian public. They wanted to show their defiance and resistance against the oppressive policies of the colonial regime.
3. Drawing Attention to the Cause: The act of throwing a bomb in the assembly was a dramatic and attention-grabbing action. It forced people to take notice of the issues being faced by the Indian people and the need for their struggle for independence.

**Relevance of the Public Safety Bill:**
The Public Safety Bill was a significant piece of legislation as it highlighted the repressive nature of British rule in India. It aimed to suppress any form of dissent or protest against British rule and curtail the rights and freedoms of the Indian people. The protest by Bhagat Singh and B.K. Dutt drew attention to the oppressive policies of the colonial government and helped galvanize support for the Indian independence movement.

**Conclusion:**
Bhagat Singh and B.K. Dutt's protest by throwing a bomb in the Central Legislative Assembly was a response to the Public Safety Bill. Their actions were motivated by their opposition to repressive laws and their desire to draw attention to the cause of Indian independence. This protest played a significant role in raising awareness about the oppressive policies of the British colonial government and inspiring others to join the struggle for freedom.