For f(x)=53x−4 and g(x)=35x+4, which of the following statements is correct?
a) f(g(x))=x for all x, but g(f(x))=x for some x
b) Neither f(g(x)) nor g(f(x)) equals x for every x
c) Both f(g(x))=x and g(f(x))=x for all x in their domains
d) g(f(x))=x for all x, but f(g(x))=x for some x