The conflict that is illustrated in this thread is not new....in fact it is very old, but probably has not yet been resolved by the authorities.
Kruger Flaps have in the past appeared in both the POF and AGK Systems exams. In at least one case the answer marked as being correct was "Leading edge flaps" although the same question included the option "Leading edge flaps close to the wing roots".
Although the CAA do not like questions being appealled, candidates must appeal in cases where a question has two correct answers. Even if publicly available databases have what was once the correct answer, there is no way of knowing that the views of the authorities have not changed.
The CAA have recently withdrawn the facility whereby FTOs could participate in the appeals process. They claimed that this was due to pressure of work but it probably had more to do with a wish to make it harder for FTOs to gain knowledge about changes to questions.
If a question has two correct answers a candidate who simply selects one of them has a 50% chance of getting the mark. But if he/she also appeals the question then the probability of getting the mark is much greater (though still sadly not 100%).