A patient was administered epidural anaesthesia with 15 ml of 1.5% lignocaine with adrenaline for hernia surgery.He developed hypotension and respiratory depression within 3 minutes after administration of block.The commonest cause would be

• A. Allergy to drug administered
• B. Systemic toxicity to drug administered
• C. Patient got vasovagal shock
• D. Drug has entered the sub arachnoid space