What began as one student's viral complaint about a mismatch between the physical and digital copies of his Grade 12 physics answer sheet has snowballed into a major controversy around one of India's biggest and most important school-leaving exams. Days after the government-run Central Board of Secondary Education (CBSE) announced its Grade 12 - equivalent to UK's A level - results, dozens of students complained about errors in their marks allegedly linked to a newly-launched digital evaluation