The Rowlatt Act was passed to curtail the nationalist and revolutionary activities. It was an act passed by the British government in India in 1919. The act was named after Sir Sidney Rowlatt, a British judge who headed the committee that recommended its implementation. The act aimed to control the nationalist movements and suppress any rebellious activities in India.

Option 1: The Rowlatt Act was not passed to bring about agrarian reforms. It was primarily focused on suppressing dissent and nationalist activities, rather than addressing agricultural issues.

Option 3: The act also did not aim to have a favorable balance of trade. Its primary goal was to maintain British control over India and prevent any uprising against British rule.

Option 4: The act was passed before the Second World War, so it cannot be related to putting war criminals on trial. This option is completely unrelated.

In conclusion, the correct answer is option 2, as it accurately reflects the purpose of the Rowlatt Act to curtail nationalist and revolutionary activities in India.