**Core Concept**
Fine-needle aspiration cytology (FNAC) is a diagnostic tool used to evaluate the nature of a lesion. It involves the insertion of a thin needle into the lesion to collect a sample of cells for further analysis. In the context of FNAC, the goal is to distinguish between benign and malignant lesions.

**Why the Correct Answer is Right**
The correct answer depends on the specific context of the lesion being evaluated. However, in general, FNAC is used to identify the presence of malignant cells, which are characterized by features such as nuclear atypia, mitotic activity, and loss of cellular cohesion. The presence of malignant cells is a critical finding that has significant implications for patient management and treatment.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is not a characteristic of FNAC findings. While FNAC can provide information on the cellular morphology, it is not typically used to evaluate the architectural pattern of a lesion.

**Option B:** This option is not a specific finding in FNAC. While FNAC can provide information on the cellular composition of a lesion, it is not typically used to evaluate the presence of specific cellular markers.

**Option C:** This option is not a characteristic of FNAC findings. While FNAC can provide information on the cellular morphology, it is not typically used to evaluate the vascular architecture of a lesion.

**Clinical Pearl / High-Yield Fact**
When interpreting FNAC results, it is essential to consider the clinical context and the specific findings on the cytology report. A high index of suspicion for malignancy should be maintained when evaluating lesions with atypical cytological features.

**Correct Answer: C.**