**Core Concept**
The correct staging of oral carcinoma involves assessing the primary tumor (T), lymph node involvement (N), and distant metastasis (M). The TNM staging system is widely used for this purpose, where T represents the size and extent of the primary tumor, N represents the involvement of regional lymph nodes, and M represents the presence of distant metastasis.

**Why the Correct Answer is Right**
In this case, the primary tumor is located on the right lateral aspect of the tongue, but the lymph node involvement is on the left side of the neck, specifically a 4 cm size lymph node at level 3. This is consistent with the N3 classification, which indicates a single lymph node 6 cm or larger in greatest dimension, or multiple lymph nodes, any of which are 6 cm or smaller in greatest dimension. The correct stage for this patient would be T1 or T2 (depending on the size of the primary tumor) N3.

**Why Each Wrong Option is Incorrect**
* **Option A:** This option is likely incorrect because the lymph node involvement is on the left side of the neck, not the right side, which would not match the N3 classification.
* **Option B:** This option might be incorrect because it does not specify the correct lymph node classification based on the given information.
* **Option D:** This option is likely incorrect because it does not provide a clear explanation for the staging of the patient's carcinoma.

**Clinical Pearl / High-Yield Fact**
When staging oral carcinoma, it's essential to accurately assess the primary tumor and lymph node involvement to determine the correct TNM classification. The location of the primary tumor and lymph node involvement can significantly impact the staging and treatment plan.

**Correct Answer:** C.