Which of the following are context-free grammars? G= ([S, A, C], [c, d, e), S, P) S rightarrow Ac|Cd A rightarrow cA|ee C rightarrow cCcc|ed G =([S, A], [a, b], S, P) S rightarrow aSa|bAa|b A rightarrow aAc| bb G = ([S, A, B), [a, b], S, P) S rightarrow AbbA|Sa|Ba A rightarrow aAb|ab Ba rightarrow Aa|b G = ((S), [a, b, c], S, P) S rightarrow aBA|aSa| lambda A rightarrow aA|bb B rightarrow BS|a G = ([S, A, B], (a, b, c), S, P) S rightarrow aS|AAb|Ba AA rightarrow Bb|ac B rightarrow BB|a