Hi student,

It is okay even if you didn't challenge the questions because if there is a bonus question, then four marks will be given to all students regardless of their response. If there are changes in answer key(due to earlier answer to some question in the answer key being wrong)  then 4 marks will be given to those who gave the correct answer and zero marks to those who did not attempt the question and -1 marks to those who gave the wrong answer.

Good luck