About Lighting and reflection of the trailer: which statement is WRONG?
White front position lights are required only if the trailer is wider than 1,60 metres.
A trailer only needs a fog light if it was put into service after 31 December 1997.
The red TRIANGULAR reflectors belong at the REAR; at the front are white (non-triangular) retroreflectors.
White retroreflectors belong at the FRONT; at the rear are red triangular reflectors.
Explanation
Book p.232 - this trailer itself must always have a rear fog light. The only exception is if the TOWING vehicle itself has no fog light. The law does contain a date nuance for older heavy trailers, but the exam follows the book: treat the rear fog light as always mandatory.