The Rowlatt Act aimed at imprisonment without trial and summary procedures for trial.

The Rowlatt Act, also known as the Anarchical and Revolutionary Crimes Act of 1919, was a law passed by the British government in India that aimed at suppressing political dissent and revolutionaries in India. The Act authorized the government to imprison anyone suspected of terrorism or revolutionary activities without trial for up to two years. It also allowed for summary procedures for trial, which means that the accused did not have the right to a trial by jury or the right to appeal.

The Act was widely opposed by Indians and sparked protests and demonstrations across the country, including the Jallianwala Bagh massacre in Amritsar, where British troops fired on unarmed protesters, killing hundreds of people. The Rowlatt Act was one of the major factors that contributed to the rise of the Indian independence movement and the demand for self-rule in India.

Therefore, the correct option is "imprisonment without trial and summary procedures for trial".