Consider the grammar G and the language L:

G: S AB | a | abC, A b, C abC | c

L: {w | w a string of a's, b's, and c's with an equal number of a's and b's}.

Grammar G does not define language L. To prove, we use a string that either is produced by G and not contained in L or is contained in L but is not produced by G. Which string can be used to prove it?

a) abac

b) caca

c) bababa

d) abababc

Please explain me