Hi Salil!! Hope you are doing well!! You have got your result and you have passed in all your subjects (with grace) and it's a great thing. But if you are confident that you will surely get increased marks in that subject ,then only apply for reevaluation , because sometimes ,marks also get decreased and may be you won't get proper grace also. So, think carefully and see whether it's necessary or not, you will spend money also and if you not get the outcome, then it's a waste. But if you have confidence on your answer and you know you will get more marks then surely go fir it and give your paper fort re-evaluation. You can consult your teacher also for this.