\[\boxed{\mathbf{174.}}\]
\[\textbf{а)}\ A \rightarrow C;\]
\[C \rightarrow A.\]
\[\textbf{б)}\ D \rightarrow A;истинно;\]
\[A \rightarrow D;ложно.\]
\[\textbf{в)}\ E \rightarrow C;\]
\[C \rightarrow E.\]