Can we draw the following hypothesis from the context (see options)? 

Context:

New Boss<br>My niece's new boss started this week. He is a manager from another state division. He started showing up at 7 Am, 1/2 an hour before starting. He asked his staff to do the same. They filed a union grievance.

Hypothesis: They have never filed a grievance before. 
Select from:
[a]. Yes.
[b]. It's impossible to say.
[c]. No.