Which of the following grammar rules violate the requirements of an operator grammar?
(i) $A \rightarrow B c C$
(ii) $A \rightarrow d B C$
(iii) $A \rightarrow C / \in$
(iv) $A \rightarrow c B d C$
(A) (i) only
(B) (i) and
(C) (ii) and (iii) only
(D) (i) and (iv) only