**Core Concept**
Leprosy, also known as Hansen's disease, is a chronic bacterial infection caused by Mycobacterium leprae that primarily affects the skin, mucous membranes, and peripheral nerves. Neural involvement is a hallmark of the disease, leading to various sensory and motor deficits.

**Why the Correct Answer is Right**
In leprosy, neural involvement occurs due to the direct invasion and replication of M. leprae within the peripheral nerves. This results in damage to the nerve fibers, leading to symptoms such as numbness, tingling, and weakness. The bacteria target the Schwann cells, which are responsible for myelination and maintenance of the nerve fibers. As the disease progresses, the neural damage becomes irreversible, and the affected nerves atrophy, leading to permanent disability. In all forms of leprosy, there is some degree of neural involvement, which can range from mild to severe.

**Why Each Wrong Option is Incorrect**
**Option A:** This option underestimates the severity of neural involvement in leprosy. While some patients may have minimal symptoms, neural damage is a universal feature of the disease.
**Option B:** This option is still too low, as even in the early stages of leprosy, there is evidence of neural involvement. The bacteria begin to replicate within the nerves, leading to damage and dysfunction.
**Option C:** This option is closer to the truth, but still underestimates the extent of neural involvement. While some patients may have mild symptoms, the majority will experience significant neural damage as the disease progresses.

**Clinical Pearl / High-Yield Fact**
It's essential to remember that leprosy is a treatable disease, but prompt diagnosis and treatment are critical to preventing irreversible neural damage and disability. The World Health Organization recommends a multidrug therapy regimen for leprosy, which includes rifampicin, clofazimine, and dapsone.

**Correct Answer:**
✓ Correct Answer: D. 100%