We have seen a lot of feedback from Oxford as well as other places, and whilst it is often representative of the questions in the question bank, in many cases the answers provided by the college are wrong. Sometimes this is the four options being wrong, but in many cases they just have the incorrect answer. We found this to be particularly true with Instruments, Comms, and Law.
Feedback questions are of course very valuable, but I would say beware of them and by no means place too much reliance on them. You must have a basic understanding of the subject otherwise you will not be able to apply the knowledge if the real exam question differs from what you are expecting.
Out of interest how is the Instruments pass rate at Oxford these days?
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CW
The original not the imposter!