Which is used for used for people animals and things. Also to selecting thing or persons out of a definite group.
Example of Interrogative pronouns Which
Will you tell me which cup to take?
I asked her which answer was right?
Which of you will go with him?
Here are the beers. Which is yours?
I can’t say which I like better.
Which of these two will you have?
Say which book you prefer.
Which way shall we go?

Interrogative Pronouns – Which ?