Wheat, barley and gram are Rabi season crops. Rabi crop or Rabi harvest refers to an agricultural crop sown in winter and harvested in the summer season. The common examples are wheat and barley. 

The dam on the river Mahanadi is the longest dam in the world. Hirakud Dam is built across the Mahanadi River, about 15 km from Sambalpur in the state of Orissa in India. Built in 1957, the dam is one of the world's longest earthen dams. Behind the dam extends a lake, Hirakud Reservoir, 55 km long. Hirakud Dam is the longest man-made dam in the world, about 26 km in length. 

Option (3) is correct.

Option (4) is correct.

Glacier ice crystals can grow as large as baseballs. It occurs in areas having a permanent cover of snow and ice. Glacial ice often appears blue when it has become very dense. A glacier is a large persistent body of ice that forms where the accumulation of snow exceeds its ablation over many years, often centuries. 

Damodar valley project serves Jharkhand and West Bengal. The Damodar river spans over an area of 25,000 km² covering the states of Jharkhand & West Bengal. So the project is meant for these two states only. 

The Himalayan forests are an example of Temperate deciduous forests. The Western Himalayan broadleaf forests is a temperate broadleaf and mixed forest ecoregion which is found in the middle elevations of the western Himalayas, including parts of Nepal, India, and Pakistan. The Eastern Himalayan broadleaf forests is a temperate broadleaf forest ecoregion found in the middle elevations of the eastern Himalayas, including parts of Nepal, India, and Bhutan. 

Laterite soil is acidic in nature. Laterites are soil types rich in iron and aluminium, and formed in hot and wet tropical areas. Nearly all laterites are rusty-red because of iron oxides. They are developed by intensive and long-lasting weathering of the underlying parent rock.

Elephant is not found in Dudhwa National Park. Dudhwa National Park is a National Park and major part of the Dudhwa Tiger Reserve located in the Terai of Uttar Pradesh state, India. It covers an area of 680 km² (260 sq mi), with a buffer zone of almost 190 km² and elephants are not found there. 

The National Research Centre on Plant Biotechnology (NRCPB) was established in 1985 with a vision to impart the biotechnology advantage to the much-needed thrust to Indian Agriculture.  

1921 is known as the year of great divide in the demographic history of India. In India, 1921 marks the start of consistent population growth as revealed by the census, after decades of alternating growth and contraction or stagnation. In fact, the change dates from 1920 with the passing of the influenza pandemic. 

Option (2) is correct.

Rice and millet crops are associated with Kharif season. Kharif crop refers to the planting, cultivation and harvesting of any domesticated plant sown in the rainy (monsoon) season in the Asian subcontinent. Some of the common examples of such crops are millet and rice. 

Jute cultivation in India is mainly practiced in West Bengal, Bihar and Assam.  

Option (4) is correct.

Intense evaporation causes saline soil. Such soil can be expected in tropical desert region. In tropical desert region the soils tend to be sandy, rocky and have low organic matters. Such soils causing intense evaporation are saline soils. 

Option 3 is correct.

Red soil is primarily found in Tamil Nadu, Andhara Pardesh and Karnataka. Red soil is mostly found in Tamil Nadu, Karnataka, parts of Maharashtra, Andhra Pradesh, MP, Orissa and Jharkhand. Crops such as cotton, wheat, rice, millets, pulses and tobacco can be grown in it. 

The peninsular plateau is sub-divided into 2 parts, namely Deccan Plateau and Central Highlands. 

Gujarat has the longest coastal area. Gujarat is situated on the west coast of Indian peninsula. The state is bound by the Arabian Sea on the west, Pakistan and Rajasthan in the north and northeast, Maharashtra in the south and Madhya Pradesh in the southeast. 

Black soil is mainly found in India in Madhya Pradesh, Gujarat, Tamil Nadu, and Karnataka. Black soil is black in color. It has been formed from lava rocks. It is also called black lava soil. Black soil is found in Deccan Trap which covers large areas of Maharashtra, Gujarat and Madhya Pradesh. It is suitable for cotton, sugarcane, wheat, millets, tobacco and oilseeds. 

Option (1) is correct.

Raniganj is popular for coal mine and related business have sprung up making Raniganj as a very popular market place. Cluster of medical practice nor make Raniganj a medical hub. Raniganj is also popular as a commercial business district serving as a link between supplies to state capital Kolkata from northern parts of the country. 

Silk weaving is common between Mysore, Bangalore, Salem and Amritsar. Silk reeling, twisting and weaving is common in all the four states.  

Tuticorin, Chennai and Ennore are the major ports on the East coast of India.