**Core Concept**
The treatment of laryngeal carcinoma involves a multidisciplinary approach, considering the cancer's extent, location, and the patient's overall health. In cases where the tumor extends to the supraglottic region and involves vocal cord fixation, a thorough evaluation of lymph node involvement is crucial for determining the optimal treatment plan.

**Why the Correct Answer is Right**
For laryngeal carcinoma with supraglottic extension, vocal cord fixation, and a solitary ipsilateral lymph node, the treatment of choice is a total laryngectomy with neck dissection. Total laryngectomy involves the removal of the larynx, which is essential for controlling the cancer in this advanced stage. The neck dissection is performed to address the solitary lymph node and prevent further lymphatic spread. This approach allows for the removal of both the primary tumor and the involved lymph node in a single surgical procedure.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because a partial laryngectomy would not be sufficient for a tumor with supraglottic extension and vocal cord fixation, as it would not address the cancer's extent in the supraglottis.

**Option B:** This option is incorrect because a supraglottic laryngectomy alone would not be adequate for a tumor with vocal cord fixation, as it would not address the involvement of the vocal cord.

**Option C:** This option is incorrect because radiation therapy alone would not be sufficient for a tumor with vocal cord fixation and supraglottic extension, as it would not address the need for surgical removal of the tumor and involved lymph node.

**Clinical Pearl / High-Yield Fact**
In the management of laryngeal carcinoma, the extent of tumor invasion and the presence of lymph node metastasis are critical factors in determining the optimal treatment plan. A thorough preoperative evaluation, including imaging studies and endoscopic examination, is essential for determining the extent of disease and planning the appropriate treatment.

**Correct Answer:** C. Total laryngectomy with neck dissection.