Is it permissible to deny a student a full mark in an exam, arguing that perfection belongs to Allah, while taking into consideration the student's effort and studying?

"While this statement is correct, its use here is out of place. One who deserves full marks should not have them reduced without a valid reason, as that would be an injustice and could demotivate the student. It is not wise to mention this matter publicly; rather, it is more appropriate for the student to inform her guardian to speak with the administration."