**Core Concept:** Rosettes are a characteristic feature of specific types of tumors in histology, particularly in neuroendocrine tumors. They are formed by the arrangement of cells around a central lumen, resembling a flower or a rose.

**Why the Correct Answer is Right:** The correct answer, **C. Ewing's sarcoma**, is a malignant tumor that originates from primitive neuroectodermal cells. In histopathology, Ewing's sarcoma exhibits a uniform, small, round cell morphology with rosette-like structures called "neuroectodermal rosettes" or "Ewing's bodies." These rosettes are formed due to the arrangement of cells around a central lumen, which helps distinguish it from other tumors.

**Why Each Wrong Option is Incorrect:**

A. **Neuroblastoma** is a malignant tumor arising from neural crest cells. Unlike Ewing's sarcoma, neuroblastoma cells do not form rosettes, and the tumor exhibits a more diverse morphology.

B. **Rhabdomyosarcoma** is a malignant sarcoma arising from skeletal muscle cells. Similar to neuroblastoma, rhabdomyosarcoma cells do not form rosettes.

D. **Lymphoma** is a malignant lymphoid neoplasm characterized by the proliferation of lymphoid cells. Lymphomas do not form rosettes, and their histopathology is distinct from Ewing's sarcoma.

**Clinical Pearl:** Recognizing the presence of rosettes in histopathology helps differentiate between various tumors, such as Ewing's sarcoma, neuroblastoma, rhabdomyosarcoma, and lymphoma. Adequate knowledge of histopathology and tumor cell characteristics is crucial for accurate diagnosis and patient management.