plz help me

 Use only Blue Pen

better to use blue pen only.... in my place also black is not allowed..... be ensure that please keep with you atleast 3 to 4 pens of same type and same clarity.... don't  change the pen having different clarity in between the exams.... You may use ink pen also...

well there is two option

1- use black pen or

2- blue pen

thats it

no one can prevent you