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Firstly sorry if this has already been answered - I did look I promise.
Secondly sorry if the answer to this is blatently obvious! In the process of trying to optimise my landing pages, I am using On Page Optimisation reports.  I have several (ok lots) with F grades which is not surprising as the landing page is not the landing page optimised for a certain keyword.  If I change the landing page to the one that I have for a certain keyword then hey presto A or B grade (clever me)! Now here's the thing - presumably the landing page that is listed by default is the one that Google "sees" for a particular keyword.  How do I change this if I can or do I have to be patient or am I just being plain daft?! Many thanks