Be (someone's) call idiom
If it's your call, it's eventually up to you to make a decision or a choice.
Though the CEO really wants to hire his brother, the selection is not his call but the HR department's call.
We can go wherever you want, either to France or Italy - it's your call.
It's not my call to tell you where you should study. You have to make that decision by yourself.
The verb "be" should be conjugated according to its tense.