I have opted both Psychology and Sociology.
psychology is a 200 marks subject while sociology is that of 100. So you have to take one more subject with sociology in case of replacement...
Psychology is really interesting and it took me only a week to cover both papers. Sociology is also easy but syllabus for sociology is quite open and mostly from current scenario... If one have a good grip and interest in on going events he should go for sociology...
See what suits you better...
Choice and decision is yours.
Good luck

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At a certain point in our lives...our lives become controlled by fate. That's the world's greatest lie.