Choosing your a-levels is a key moment in your life.
It is the best opportunity to start off and show potential employers and universities that you are knowledgeable and focused on what you can do with your future.
You could do something specialised like a degree in conservation biology and ecology where you would need: biology, chemistry, geology, geography, mathematics..
.. or civil engineering where you would want: chemistry, economics, geology, mathematics, physics.
conservation biology and ecology, and civil engineering are specialised that opportunities at Ph.D. are available and with that you can work in specialised consultancies and government agencies and international opportunities.
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On the flip-side you can choose subjects which are adaptable for many positions within a local society like government or police or business or the media
economics, government and politics, geography, law, psychology, sociology
where you can go from an administrator in government to working your way up to maybe how the council deals with health or education or roads or the economy and the same starting as a special constable on the streets to working your way up to dealing with crime statistics and behaviour changes and in business you might start in customer service and end up head of procurement or marketing and again becoming a trainee reporter and eventually becoming an editor and all these senior positions could be within a town who might of all been educated at the local schools and would have studied the same similar subjects and so can converse and understand and play their role in the local community.
So this point now is a brilliant opportunity to become something so think about what you want to dedicate your life to?
Animals? the environment? law and community? media and society? business and economy?
You will find many opportunities within that something you dedicate yourself to but similar subjects mean you can change career path but changing career is not an easy task and one that takes time to develop but say you worked in local government for some years and then in business and then worked in media all of this would complement your career.