**Question:** Local anaesthetic used for nasal surgery

**Core Concept:** Local anaesthetics are drugs that are used to block nerve impulses, preventing pain and sensation. They work by inhibiting the sodium channels in neurons, preventing the flow of sodium ions and thus depolarization of the neuron.

**Why the Correct Answer is Right:**
Local anaesthetic C is chosen as the correct answer because it is the most commonly used local anaesthetic for nasal surgery. Caine is a combination of lidocaine and adrenaline, which provides better hemostasis (reduced bleeding) during the procedure.

**Why Each Wrong Option is Incorrect:**

A. Lidocaine (Option A) is a local anaesthetic, but it is not specifically used for nasal surgery. Adrenaline is combined with lidocaine in caine to enhance hemostasis.
B. Diclofenac (Option B) is a nonsteroidal anti-inflammatory drug (NSAID) used for analgesia, not local anaesthesia.
D. Dexamethasone (Option D) is a corticosteroid used to reduce inflammation and edema, not for local anaesthesia.

**Clinical Pearl:**

During nasal surgery, the use of caine (lidocaine with adrenaline) provides effective anaesthesia while reducing bleeding. This combination is a commonly used local anaesthetic for nasal procedures.

**Correct Answer:** Caine (lidocaine with adrenaline)

**Correct Answer: [Letter] Caine**