Which condition is described as a rare progressive disorder in which motor neurons deteriorate?

• A. Cerebral Palsy
• B. Parkinson's Disease
• C. Motor Neurone Disease
• D. Multiple Sclerosis

Answer: (C)

Motor neurone disease describes a rare, progressive disorder in which the motor neurons—the nerve cells that carry commands from the brain to the muscles—deteriorate and die. As these neurons fail, signals to voluntary muscles weaken, leading to increasing muscle weakness and wasting. Over time, this affects speaking, swallowing, walking, and eventually breathing as respiratory muscles become involved. This pattern of gradual motor decline is what makes this condition the best fit for the description.

Cerebral palsy results from early brain damage and is typically non‑progressive in nature, so it doesn’t involve ongoing motor neuron degeneration. Parkinson’s disease involves loss of dopamine-producing neurons in a specific brain region, causing tremor and stiffness rather than a widespread degeneration of motor neurons controlling muscles. Multiple sclerosis is an autoimmune disease that damages the myelin sheath in the central nervous system, producing a broad range of symptoms but not primarily motor neuron deterioration.