**Core Concept**
Japanese Encephalitis (JE) is a viral disease caused by the JE virus, primarily transmitted through the bite of an infected mosquito, specifically the Culex species. It is a significant cause of viral encephalitis in Asia and has a notable mortality rate, although it is not as high as 90-100%.

**Why the Correct Answer is Right**
The correct answer, 90%-100% mortality rate, is incorrect. The actual mortality rate of Japanese Encephalitis is significantly lower, ranging from 20% to 30% in non-immune individuals. This discrepancy is crucial for understanding the disease's severity and the importance of vaccination and preventive measures. The JE virus primarily affects the central nervous system, leading to inflammation of the brain (encephalitis) and, in severe cases, death.

**Why Each Wrong Option is Incorrect**
**Option A:** Man-to-man transmission of Japanese Encephalitis is not reported, which is true. The virus is primarily spread through the bite of an infected mosquito.
**Option B:** The Culex mosquito is indeed the primary vector for Japanese Encephalitis, transmitting the virus to humans through its bite. This statement is correct.
**Option D:** There is no rash or local lesion typically associated with Japanese Encephalitis, making this statement correct as well.

**Clinical Pearl / High-Yield Fact**
It is essential to note that Japanese Encephalitis is a vaccine-preventable disease. The JE vaccine is recommended for individuals traveling to or living in endemic areas, particularly those who will be spending time outdoors or in rural areas where mosquito-borne diseases are more common.

**✓ Correct Answer: C. 90%-100% mortality rate**