The southern part of the Aravalli hills is known as the Mewat hills.

The Aravalli Range is one of the oldest mountain ranges in the world, stretching across northwestern India. It runs through several states, including Rajasthan, Haryana, and Delhi.

The southern part of the Aravallis, specifically in Haryana, is known as the Mewat Hills. This region is named after the Mewat area, which is a geographical and cultural region that spans parts of Haryana, Rajasthan, and Uttar Pradesh. The Mewat hills are characterized by hilly terrain and are a continuation of the Aravalli range as it extends southward.

The other names you mentioned — Marshal Hills, Bhangar, and Yamunanagar — are not associated with the southern part of the Aravallis specifically. While Yamunanagar is a city located near the Aravallis, it is not a name used for the southern portion of the range.

1. Aravalli Range Overview

The Aravalli range stretches from the northwest (near Delhi) to the southeast (in Gujarat), spanning across several states. It is one of the oldest mountain ranges in the world, formed more than 2.5 billion years ago. The range is crucial to the geography of northern and western India and has both ecological and cultural significance.

2. Southern Part of the Aravallis

The Aravallis are split into two sections: the northern part and the southern part. The southern part of the Aravallis extends primarily through the state of Haryana, and it continues into parts of Rajasthan.

• The southern part of the range is known for its hilly terrain, rugged topography, and forest areas.
• This region also has significant biodiversity, with flora and fauna adapted to both the hills and the plains around them.

3. Mewat Hills

The Mewat Hills are part of this southern section of the Aravallis. Mewat is a historical and cultural region that lies across the states of Haryana, Rajasthan, and Uttar Pradesh.

• The Mewat region is located south of Delhi, encompassing areas in Haryana (notably around the districts of Mewat and Nuh) and parts of Rajasthan.
• The Mewat Hills are found in this region, marked by low, rounded hills that are an extension of the Aravallis.
• These hills are known for their rural and semi-arid landscape, which is significantly different from the higher, more rugged northern sections of the Aravalli range.

Hence option B is correct.

Tosham Hills are located in Bhiwani district, Haryana. They are known for their historical significance and scenic beauty.

Tosham Hills are a range of low hills situated in the Bhiwani district of Haryana, India. They are part of the Aravalli Range, which is one of the oldest mountain ranges in the world. Tosham Hills are historically significant because they house a variety of ancient rock carvings, inscriptions, and temples, making them a site of archaeological importance.

• The hills are particularly known for their association with the Jain religion. There are temples and inscriptions that suggest a connection with Jain saints and the spread of Jainism in ancient times.
• In addition to their religious significance, the hills are also famous for their rock-cut architecture and caves, which were possibly used for meditation or as shelter by ancient communities. In terms of natural beauty, the Tosham Hills offer a serene and picturesque landscape. The area around the hills is dotted with villages and is also home to a variety of flora and fauna, which adds to its charm.

The Tosham Hills attract tourists, historians, and archaeologists alike due to their cultural and historical richness. They also hold a place in local folklore and are seen as a part of Haryana's heritage. Would you like to explore any particular aspect of Tosham Hills further, such as the history, geology, or any specific sites there? 
 

The Tosham Hills, like much of the Aravalli range, support a range of wildlife, including species of birds, reptiles, and small mammals. Although the region has a semi-arid climate, it still sustains some vegetation, including scrub forest and grasslands, which attract a variety of animals.

• The flora and fauna of Tosham Hills contribute to its ecological importance, and the area is sometimes explored by those interested in wildlife or natural history.

The climate around the Tosham Hills is typically hot and dry, with summer temperatures soaring high. Winters are cooler, making it a more comfortable time to visit.

• The terrain of Tosham is marked by rocky outcrops, low hills, and narrow valleys, contributing to the area's unique landscape. It’s a great place to explore on foot, allowing visitors to get a close-up view of the geological formations and natural features.

Hence option D is correct.  

In the above question, the following are correct :

(a) There is another branch of Aravali which extends from Haryana to Delhi. This branch is known as Delhi Ridge.

(b) The main stretch of Aravali hills is found in the Gurugram district.

(c) The Southern part of Aravali hills is locally known as Mewat hills.

Hence the correct option is D.