Make it up
I guess you are honest and that's good, but you don't have to show them your passport, so just tell them what they want to hear. You don't need to lie, just when they say "What nationality are you?" reply with the question "What nationality are your other tenants?" When they say "filipino or Indian or Antarctican or whatever" just say " Oh, I think I will fit in just fine and be very happy there"