"The Computing A Level is not intended as a programming course but a course that covers the fundamentals of computing of which programming (and problem solving) form a key component."
I'd say that C is a key component of computer science; it is the closest thing to the hardware withholding assembly and machine code.
I think schools should teach C, Lisp, and Python. Paul Graham tells it well in his "The Roots of Lisp" essay (http://www.paulgraham.com/rootsoflisp.html), where he asserts that C and Lisp are the two clean programming constructs in which languages of the future will be based off (and this has held true in my opinion). Python falls in the middle of C and Lisp and thus is a useful comparison (and everyday-living) language.