hey,

let me know you the correct scenario , if a student getting fail or getting pass is directly proportional to the content he is written in his answer sheet , if you have written enough good then examiner will make you pass and if not then sorry to say even examiner wont able to safe you .

talking about if a student gets failed by just 2-3 marks then yes a student can if he/she didn't even attempted all the questions and haven't written relevant answers asked in questions

hope you find it informative!