Morgan, a Charge Nurse, Voted in a Union Election in Her

Morgan, a charge nurse, voted in a union election in her former job.Now, in a different organization, she has been told that she is ineligible to vote.Why can't she vote?

A) NLRB has ruled that health care workers can no longer be unionized.
B) Part time workers are not eligible to vote.
C) Management considers her a supervisor - she makes independent decisions in guiding the actions of other nurses.
D) Employees may only vote in one union election.
E) The union says that charge nurses should not be part of the bargaining unit.