Explanation: The Eastern Ghats and Western Ghats are two significant mountain ranges in India that run parallel to the eastern and western coasts, respectively. The Eastern Ghats extend from the Mahanadi River in Odisha to the Kaveri River in Tamil Nadu, while the Western Ghats run along the western edge of the Indian peninsula from the Tapti River in Gujarat to the Kanyakumari in Tamil Nadu.
In Andhra Pradesh, the Eastern Ghats are a prominent feature, and they intersect with the Western Ghats in the southern part of the state. This intersection is marked by the Nigiri hills, which are a part of the Eastern Ghats. The Nigiri hills are significant not only for their geographical location but also for their ecological importance. They form a unique ecological zone where the flora and fauna of both the Eastern and Western Ghats converge, creating a rich biodiversity.
The Nigiri hills are located in the border region of Andhra Pradesh and Tamil Nadu, specifically in the Chittoor district of Andhra Pradesh. This area is known for its dense forests, waterfalls, and diverse wildlife. The hills are a part of the Eastern Ghats but are situated in a transitional zone where the Eastern Ghats meet the Western Ghats, making them a crucial geographical feature in the context of Andhra Pradesh's topography.
Understanding the geographical features of Andhra Pradesh, particularly the intersection of the Eastern and Western Ghats, is important for comprehending the state's ecological and environmental characteristics. The Nigiri hills, being the specific location where these two major mountain ranges meet, are a key geographical landmark in Andhra Pradesh and are often highlighted in geographical studies and examinations related to the state's geography.
In summary, the Nigiri hills are the correct answer as they are the specific geographical feature where the Eastern and Western Ghats intersect in Andhra Pradesh, marking a significant ecological and geographical zone.