You Have Been Summoned as a Prospective Juror,and Are Being

You have been summoned as a prospective juror,and are being asked questions by the Crown and defence.When the defence finds out you are taking a course in forensic psychology,he argues that you should be excused on this basis and not eligible to be a juror in this case.What type of challenge is the defence council using in this situation?

A) Ex-post-facto challenge
B) Challenge for cause
C) Nullification challenge
D) Voir dire challenge
E) Peremptory challenge