**Core Concept**
Diffuse large B-cell lymphoma (DLBCL) is a type of non-Hodgkin lymphoma (NHL) characterized by its aggressive behavior and rapid progression. It is the most common and malignant form of NHL, accounting for approximately 30% of all NHL cases.

**Why the Correct Answer is Right**
DLBCL arises from the proliferation of malignant B cells, which exhibit an abnormal pattern of growth and differentiation. These cells often express the B-cell marker CD20 and can be positive for the B-cell-specific protein MUM1. The pathogenesis of DLBCL involves genetic alterations, including mutations in the c-MYC gene, which leads to the overexpression of the c-MYC protein. This protein plays a crucial role in cell proliferation and apoptosis, contributing to the aggressive behavior of DLBCL.

**Why Each Wrong Option is Incorrect**
**Option A:** Follicular lymphoma is a type of NHL, but it is generally less aggressive than DLBCL and has a more indolent course.
**Option B:** Mantle cell lymphoma is another type of NHL, but it is characterized by its distinctive morphological features and is not as aggressive as DLBCL.
**Option C:** Burkitt lymphoma is a highly aggressive form of NHL, but it is more common in children and is often associated with the translocation t(8;14).

**Clinical Pearl / High-Yield Fact**
DLBCL is often diagnosed in patients over the age of 60, and it has a poor prognosis if left untreated. Early diagnosis and treatment with chemotherapy and/or radiation therapy can improve outcomes, but relapse is common.

**Correct Answer: C. Burkitt lymphoma is a highly aggressive form of NHL, but it is more common in children and is often associated with the translocation t(8;14).**