What should I consider when joining the marines as an officer?

I am looking at joining the Royal Marines as an officer if that doesn't work then the Grenadier guards again as an officer. I have yet to take my GCSEs and would like advice for what ones a recruiter would find most appealing I would also like some advice for A-levels. I would also like to know about any catches or what my job as a combat officer would involve and would strongly appreciate comments from ex/current marines or grenadiers or indeed any member of the military. And please don't make any comments about me being to young to decide a career or any negative comments about the army's role. I'm also prepared to do what is necessary.
Asked Oct 26, 2013

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