Hey student,

No , in 2019 board exams u cannot use black pen in exams or any other colors pen and you can only use blue pen or royal(gel) blue pen before 2019 you can use black pen but now we can not because this will increase equally among students as black colour has no shades so a teacher can change answers but in case of blue pen it will be visible.

All the best student,

Hope this helps you.