Which of the Following Sets Out a Mandatory Time Limit

Which of the following sets out a mandatory time limit for a grievance procedure:

A) A grievance shall be submitted to the supervisor within five days of the incident giving rise to the matter in dispute.
B) A grievance may be submitted to the supervisor within five days of the incident giving rise to the matter in dispute.
C) A grievance shall be submitted to the supervisor within five days of the incident giving rise to the matter in dispute and any grievances submitted outside of the of the time provided are inarbitrable.
D) An employee has no grievance until they first give their immediate supervisor an opportunity to deal with their complaint.
E) A grievance should be submitted to the supervisor within five days of the incident giving rise to the matter in dispute.