The transfer function of a discrete time LTI system is given byConsider the following statements:S1: The system is stable and causal for ROC: |z| > 1/2S2: The system is stable but not causal for ROC: |z| < 1/4S3: The system is neither stable nor causal for ROC: 1/4 < |z| < 1/2Which one of the following statements is valid?

• A. Both S1 and S2 are true
• B. Both S2 and S3 are true
• C. Both S1 and S3 are true
• D. S1, S2 and S3 are all true