**Core Concept**
Russell bodies are inclusions found within the endoplasmic reticulum (ER) of plasma cells, which are a type of white blood cell involved in the production of antibodies. These inclusions are composed of immunoglobulin light chains that have accumulated due to a defect in the ER's quality control mechanism.

**Why the Correct Answer is Right**
Russell bodies are characteristic of multiple myeloma, a type of cancer that affects plasma cells. In multiple myeloma, the production of immunoglobulins is uncontrolled, leading to the accumulation of light chains within the ER of plasma cells. This accumulation forms Russell bodies, which are visible under the microscope. The presence of Russell bodies is a diagnostic feature of multiple myeloma and is associated with the production of monoclonal immunoglobulins.

**Why Each Wrong Option is Incorrect**
**Option A:** Russell bodies are not typically associated with Waldenström's macroglobulinemia, a condition characterized by the production of IgM monoclonal protein.
**Option B:** While plasma cell dyscrasias can be associated with various types of cancer, Russell bodies are specifically characteristic of multiple myeloma, not lymphoma.
**Option C:** Russell bodies are not typically seen in chronic lymphocytic leukemia (CLL), a type of cancer that affects the lymphocytes.

**Clinical Pearl / High-Yield Fact**
Russell bodies are a key diagnostic feature of multiple myeloma, and their presence can help differentiate this condition from other plasma cell dyscrasias.

**Correct Answer: D. Multiple myeloma.**