Yes! I know about all procedures and requirements which are mention in your recommended thread but questions was that for example, if there is an advertisement for the MICROBIOLOGY LECTURER post then what are the optional subjects that I suppose or recommended to choose because according to my knowledge there is a rule that the candidate must have the subject as a major to which the advertisement is given. So to my point of view I should select MICROBIOLOGY as one of my optional subjects in order to participate for this post but I didn't find MICROBIOLOGY in any of the group from A to E as an optional.