The correct answer is option 4. The Non-cooperation Movement in 1920 was withdrawn because of the violence that erupted in Chauri Chaura.

The Non-cooperation Movement was launched by Mahatma Gandhi as a peaceful protest against British rule in India. It aimed to boycott British institutions, products, and laws and promote the use of Indian-made goods and the practice of Indian culture. However, in Chauri Chaura, a small town in Uttar Pradesh, violence broke out during a protest rally. A group of protesters attacked a police station, leading to the death of 22 policemen.

Gandhi, who was deeply committed to non-violence, was shocked by this incident. He believed that the movement had lost its nonviolent character and that it was no longer feasible to continue with the protests. As a result, he made the difficult decision to withdraw the Non-cooperation Movement, emphasizing the importance of maintaining peaceful methods of resistance. This decision was seen as a setback for the Indian independence movement, but it highlighted Gandhi`s unwavering commitment to nonviolence as the means to achieve freedom.