I can't Refer you any subject it only depends on your interest and will, all of above subject are good choices and scoring too, but about indo-pak history there is little bit confusion, in previous exams since 2010 indo-pak history is bitterly disappointing the Aspirants , but if you chose indo pak history the paper of Pakistan affairs will be prepared in its syllabus, hence its syallabus covered 300marks paper. best of luck for your last subject carry on......:P