Okay, let's tackle this question about the treatment for T3N0M0 squamous cell carcinoma of the maxillary sinus. First, I need to recall the staging system for head and neck cancers. The T3N0M0 classification means the tumor is larger, invading nearby structures, but no lymph node or distant metastasis.

The core concept here is the treatment approach for locally advanced head and neck cancers. Typically, for T3N0M0, the standard is a combination of surgery and radiation, maybe with chemotherapy. But wait, the maxillary sinus is a tricky area. Surgical resection might be difficult due to its location. So maybe the mainstay is radiation therapy with concurrent chemotherapy? Or is there a role for surgery first? I remember that for some head and neck cancers, like oropharyngeal, chemoradiation is standard, but for others, surgery might be preferred. The maxillary sinus is part of the nasal cavity, so maybe the treatment is similar to other head and neck sites. But I need to confirm.

Looking at the options, the correct answer would be a combination of surgery and postoperative radiation. Alternatively, if surgery isn't feasible, then chemoradiation. But the question is about T3N0M0. If the tumor is resectable, surgery with adjuvant therapy. If not, then chemoradiation. So the answer might be a combination of surgery and radiotherapy. Let me check some guidelines. NCCN guidelines for head and neck cancers suggest that for resectable T3N0M0, surgery followed by radiation is an option. Alternatively, chemoradiation could be used if the tumor is not resectable. So the correct answer is probably surgery plus radiation. The wrong options might be options like "radiation alone" or "chemotherapy alone", which aren't sufficient for T3. Also, maybe "surgery alone" is incorrect because adjuvant radiation is needed. So the correct answer is a combination of surgery and radiation. Therefore, the correct answer is the option that includes both surgery and postoperative radiotherapy.

**Core Concept**
Squamous cell carcinoma of the maxillary sinus (T3N0M0) is a locally advanced head and neck cancer requiring multimodal therapy. Treatment depends on tumor resectability, with surgery and adjuvant radiotherapy as the standard for operable cases, and chemoradiation for non-resectable tumors.

**Why the Correct Answer is Right**
For T3N0M0 maxillary sinus carcinoma, **surgery (e.g., lateral rhinotomy or craniofacial resection) followed by postoperative radiotherapy** is the optimal approach if the tumor is resectable with clear margins. Surgery removes the bulk of the tumor, while adjuvant radiotherapy targets microscopic residual disease and high-risk areas. Concurrent chemotherapy may be added if margins are close or risk factors exist (e.g., perineural invasion), but this is not universally required for N0 disease.

**Why Each Wrong Option is Incorrect**
**Option A:** "Radiotherapy alone" is insufficient for T3 disease due to its limited ability to control locally advanced tumors.
**Option B:** "Chemotherapy alone" lacks curative intent and is not a standalone treatment for solid tumors.
**Option C:** "Surgery alone" risks

✓ Correct Answer: C. Maxillectomy and Radiotherapy