## Core Concept
The question revolves around the appropriate route for administering nutrition to a patient who is comatose for an extended period. This scenario necessitates a route that bypasses the oral route, which is not feasible in an unconscious patient. The primary goal is to ensure the patient receives adequate nutrition for recovery and to prevent malnutrition.

## Why the Correct Answer is Right
The correct answer, , involves the use of a **gastrostomy tube** or **percutaneous endoscopic gastrostomy (PEG) tube**. This method allows for direct access to the stomach, enabling the administration of nutrition, medications, and fluids. It is particularly beneficial for patients who require long-term nutritional support but cannot consume food orally. The PEG tube is inserted through the abdominal wall into the stomach under endoscopic guidance, making it a suitable option for long-term use.

## Why Each Wrong Option is Incorrect
* **Option A:** refers to the **intradermal route**, which is primarily used for diagnostic purposes, such as allergy testing or tuberculin skin testing. This route is not suitable for nutritional support.
* **Option B:** refers to the **subcutaneous route**, commonly used for insulin administration and some types of injections. While it allows for the administration of fluids and certain medications, it is not the most efficient route for providing complete nutrition over a long period.
* **Option D:** could potentially refer to other routes of administration, but without specific context, it's clear that for long-term nutritional support in a comatose patient, routes like **intravenous (IV)**, **intramuscular (IM)**, or **intradermal** are not ideal due to limitations in nutrient delivery, potential for complications, and unsuitability for prolonged use.

## Clinical Pearl / High-Yield Fact
A key point to remember is that for patients requiring long-term nutritional support, especially those who are unconscious or have difficulty swallowing, **enteral nutrition** (via a feeding tube) is generally preferred over **parenteral nutrition** (IV nutrition) due to lower risks of complications and because it maintains gut function.

**Correct Answer: C. gastrostomy tube.**