**Core Concept**
Multiple myeloma is a plasma cell dyscrasia characterized by the proliferation of malignant plasma cells in the bone marrow, leading to various clinical manifestations. One of the notable ECG abnormalities associated with multiple myeloma is a short QT interval. This is due to the excessive production of lambda light chains, which can interfere with the cardiac potassium channels, thereby altering the repolarization phase of the cardiac action potential.

**Why the Correct Answer is Right**
The short QT interval in multiple myeloma is thought to be caused by the accumulation of lambda light chains in the cardiac tissue, which can activate the inward rectifier potassium channels (Kir2.1) and increase the efflux of potassium ions. This leads to a shortened repolarization phase, resulting in a short QT interval on the ECG. The excessive production of lambda light chains in multiple myeloma can also cause other cardiac abnormalities, such as bundle branch blocks and atrioventricular blocks.

**Why Each Wrong Option is Incorrect**
* **Option A:** Chronic myeloid leukemia is characterized by the proliferation of granulocyte-macrophage progenitor cells, and it is not typically associated with a short QT interval on ECG.
* **Option C:** Chronic lymphocytic leukemia is a type of B-cell lymphoma, and it is not commonly associated with a short QT interval.
* **Option D:** Hodgkin's disease is a type of lymphoma that affects the immune system, and it is not typically associated with a short QT interval on ECG.

**Clinical Pearl / High-Yield Fact**
It is essential to note that a short QT interval in multiple myeloma can be a diagnostic clue, but it is not specific to this condition. A thorough investigation, including laboratory tests and imaging studies, is necessary to confirm the diagnosis of multiple myeloma.

**✓ Correct Answer: B. Multiple myeloma**