I will suggest criminology.
It has 4 different sections and you have to do one question from each question. Meanwhile there are repeating questions from last years.
i.e., Principles of investigation was in 2016, 2017, 2018
Juvenile Delinquency was in 2017, 2018, 2019
Few theories and few laws to remember.
PPC and CPC are two main laws you need to memorize.
One section contains social issues and your other preparation overlaps this section.
You have very limited syllabus to go through. I opted subject in 2017 and i scored 67 with 3 days work on it.