Explanation:

The Jallianwalla Bagh massacre occurred on April 13, 1919. Immediately preceding this tragic event was the passage of the Anarchical and Revolutionary Crimes Act of 1919, popularly known as the Rowlatt Act, in March 1919. This draconian act allowed the British government to imprison individuals suspected of sedition without trial, leading to widespread protests and civil unrest across India, which directly contributed to the gathering at Jallianwalla Bagh. The Partition of Bengal occurred in 1905. The Ilbert Bill controversy was in 1883-1884. The Morley-Minto Reforms (Indian Councils Act) were enacted in 1909.