While some of the questions are a little complex and require actual knowledge of driving and The Highway Code, there are other questions that're particularly easy and, in my opinion, if they're gotten wrong I think it should merit an automatic fail.
Now, I think this may sound a little harsh, and maybe it is (I hope not) but perhaps I should give you a flavour of these questions: "What is the best thing to do if you're angry before driving?" the correct answer (if I remember correctly) is "Listen to some calming music and try to relax" which is fair enough, but here are two of the incorrect answers (I forget the fourth choice): "Drink some alcohol to calm yourself down" and "Confront the person and show them how angry you really are". Personally, I think that if somebody chose either of the other two, they're likely to have serious problems and not be able to do many things (let alone driving). Drinking alcohol while angry is likely to magnify this person's feelings of anger and hatred and plus, it'll give them confidence, perhaps the confidence to go and attack the other person or something else crazy. But "Confront the person and show them how angry you really are" sounds like a downright frightening answer to me, I can imagine an enraged person shouting to his friends "I'll show him how angry I really am!" as he heads off with his murdering axe.
But that's not all; another question I remember is one about a sheep herder asking you if you can stop for a few minutes while he gets his sheep across the road. There were four choices about how to react, one of them was "Ignore him; he has no authority over you!" (Okay, I did add the exclamation mark), but are there really that many rude people out there for whom this is a reasonable answer? Do people really only do things for others if the others have authority over them? But what was the worst thing about this question was that there was no option to do what the herder asked you! The correct answer, I think, was the continue driving, but slowly (most likely so that most of the sheep can get across and you'll only run down one or two).
Finally, one of the questions was about the effects of alcohol on human beings, the three wrong options being "Increased concentration", "Heightened Reactions" and another trait found in these people who've supposedly become superhuman by drinking alcohol. If there really are people who think that these are correct choices, perhaps learning about the effects of alcohol should become part of compulsory education?
Though, perhaps the people who wrote these questions decided to have a little fun by including totally absurd answers to straight questions. I really hope that's the explanation (I imagine it'd be the only fun that question writers have in their job) because if it's not, it's a sad reflection of some people...