The trick is in the use of the word "minimum", since they didn't mention an altitude.
The well known phrase "RTFQ" rings very true, all the way from PPL to ATPL level, it is so easy to mis read the question and jump to the wrong conclusions. By doing the confuser you will hopefully start to understand the way the CAA style their questions which will help.
However there are a few questions where you have to give the CAA answer not the real answer, watch out for them
smithgd