In a parking lot in Mount road, there are six parking slots in a row numbered 1–6 consecutively. Exactly five cars of five different colours, blue, green, maroon, red and white, are to be parked in the slots according to the following conditions.
(i) The red car must be parked in slot 3.
(ii) The blue car must be parked in the slot next to slot in which the white car is parked.
(iii) The green car cannot be parked in a slot next to the slot in which the maroon car is parked.
Which of the following must be true of any acceptable parking arrangement?