**Core Concept:** Local anaesthetics are a class of drugs that are commonly used for their analgesic, anaesthetic, and antiarrhythmic properties. They are derived from natural sources, such as procaine, or synthesized chemically. Antiarrhythmic agents are medications that are used to manage or prevent abnormal heart rhythms by modulating ion channels in cardiac cells.

**Why the Correct Answer is Right:** The correct answer, D, refers to lidocaine, which is a local anaesthetic with antiarrhythmic properties due to its ability to block voltage-gated sodium channels in cardiac myocytes, leading to reduced excitability and decreased arrhythmia generation. It is classified as a Class Ic antiarrhythmic agent.

**Why Each Wrong Option is Incorrect:**

A. Amiodarone is a broad-spectrum antiarrhythmic agent, not a local anaesthetic. It belongs to Class IC and IV, acting as a beta-blocker, calcium channel blocker, and potassium channel blocker.

B. Propranolol is a beta-blocker used to treat hypertension, angina, and arrhythmias. It is not considered a local anaesthetic.

C. Verapamil is a calcium channel blocker used for treating hypertension, angina, and arrhythmias. It is a Class III antiarrhythmic agent, not a local anaesthetic.

**Clinical Pearl:** The ability of lidocaine to function as both a local anaesthetic and antiarrhythmic agent makes it a valuable tool in clinical practice, especially for managing life-threatening arrhythmias and providing regional anaesthesia.

**Correct Answer:** D. Lidocaine is a local anaesthetic with antiarrhythmic properties due to its blockade of voltage-gated sodium channels in cardiac myocytes. It is classified as a Class Ic antiarrhythmic agent and can be used to manage life-threatening arrhythmias or provide regional anaesthesia.