**Core Concept**
The core concept here is the histopathological examination of a frozen section, which reveals features characteristic of a specific type of tumor. The description points towards a lesion with features of glandular differentiation, but without true invasion into the surrounding stroma.

**Why the Correct Answer is Right**
The presence of fibrosis, cystic spaces, compressed glands with a lobular orientation, and a single layer of epithelial cells with oval nuclei suggests a well-differentiated neoplasm. The absence of true invasion into the adjacent stroma rules out malignancy. The histopathological features described are consistent with a benign tumor of glandular origin, specifically a **Pleomorphic Adenoma**. Pleomorphic adenomas are the most common type of benign salivary gland tumor and typically exhibit a mix of epithelial and mesenchymal components. The compressed glands with a lobular orientation and the lack of invasion are characteristic features of this tumor.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is not relevant to the histopathological description provided.
**Option B:** This option is incorrect as it does not match the histopathological features described in the frozen section examination.
**Option C:** This option is incorrect as it does not accurately describe the histopathological features of the tumor in question.

**Clinical Pearl / High-Yield Fact**
It's essential to remember that the diagnosis of tumors, especially those of glandular origin, relies heavily on histopathological examination. A thorough understanding of the histological features and the ability to distinguish between benign and malignant tumors is crucial for accurate diagnosis and management.

**Correct Answer:** C. Pleomorphic adenoma.