**Core Concept**
Arboviruses are a diverse group of viruses transmitted primarily by arthropods, such as mosquitoes and ticks, causing a range of diseases in humans. Understanding the transmission dynamics of these viruses is crucial for prevention and control measures.

**Why the Correct Answer is Right**
Chikungunya virus (CHIKV) is a member of the Togaviridae family, transmitted primarily through the bite of infected Aedes species mosquitoes, particularly Aedes aegypti. The virus is endemic in tropical and subtropical regions worldwide, including parts of Asia and Africa. The primary transmission vector of CHIKV is Aedes aegypti, which is also responsible for the transmission of other arboviruses like dengue and yellow fever.

**Why Each Wrong Option is Incorrect**
**Option A:** Yellow fever is not endemic in India, but rather in tropical regions of Africa and South America. India has a vaccination program in place to control yellow fever outbreaks along its borders.
**Option B:** Dengue virus has four distinct serotypes (DENV-1, DENV-2, DENV-3, and DENV-4), which can cause repeated infections, leading to increased severity and complications.
**Option C:** Kyasanur Forest Disease (KFD) was first identified in Karnataka, India, not West Bengal. KFD is a tick-borne viral hemorrhagic fever endemic to the Indian subcontinent.

**Clinical Pearl / High-Yield Fact**
Aedes mosquitoes are responsible for the transmission of several arboviruses, including dengue, chikungunya, and yellow fever. The use of insecticide-treated bed nets and elimination of breeding sites can significantly reduce the risk of transmission.

**✓ Correct Answer:** D. Chikungunya is transmitted by Aedes aegypti