To complete the interview using passive voice, let's restructure the text as follows:
Interviewer:
How is the building used today?
Owner of Cix Shirts:
The cotton for our clothes is grown in India.
Interviewer:
Where was cotton grown for the 2010 edition?
Owner of Cix Shirts:
The shirts are made in our factories in many parts of Asia.
Interviewer:
Where are the shirts sold?
Owner of Cix Shirts:
They are sold in London, Paris, and Milan.
In this conversion, we made sure the actions focus on what is done to the subjects (e.g., "is grown," "are made," "are sold"), which is the essence of using passive voice.