Indian Rivers and Waterways

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. 

Mizoram

This is the correct answer as Arunachal Pradesh has an abundance of water resources, but lacks in infrastructural development.

Gobind Sagar is a reservoir created by the Bhakra Dam on the Sutlej River in Himachal Pradesh. It is one of India's largest reservoirs. The Son, Rihand, and Narmada rivers have different dams and reservoirs.

The Narmada River originates at Amarkantak in the Maikala Range of Madhya Pradesh. Amarkantak is a unique pilgrimage site where two major rivers - Narmada and Sone - originate. The Mahanadi originates nearby but not at Amarkantak, while Damodar and Tapti originate elsewhere.

Himalayan rivers have relatively narrow basins because they flow through mountainous terrain with steep gradients (Ganga basin in plains is different). Their catchment areas in the mountains are not as extensive as peninsular rivers in terms of square kilometers. They do perform intensive erosional activity and are perennial due to glacial melt and rainfall. Statement A about narrow basins is actually true for Himalayan rivers in their mountain courses.

Peninsular rivers of India flow through the peninsular plateau and have their sources in the Western Ghats or other plateau regions. The Krishna River, along with Godavari, Mahanadi, Narmada, and Tapi, are major peninsular rivers. Gandak, Kosi, and Sutlej are all Himalayan rivers originating in the Himalayas.

Narmada is a west-flowing river that drains into the Arabian Sea, while Mahanadi, Godavari, and Krishna are all east-flowing rivers that eventually empty into the Bay of Bengal. This geographical distinction is important for Indian river systems.

The Nile River flows through Cairo, Egypt, and is famously associated with the city of Alexandria which sits on the Mediterranean coast at the western edge of the Nile Delta.

The River Scheldt flows through the city of Antwerp in Belgium. It is a major river that runs through northern Belgium and the Netherlands, emptying into the North Sea.

The Menam (Chao Phraya) River flows through Bangkok, Thailand. It is the main river of Thailand and runs through the center of Bangkok, the country's capital city.

The Danube River flows through Budapest, making it one of the great European capitals built on this iconic waterway. The Danube is Europe's second-longest river and passes through multiple capitals including Vienna, Bratislava, and Belgrade before reaching the Black Sea. The Spree flows through Berlin, while 'Dimbovitya' and 'Plat' are either misspelled or fictional names.

The Danube River flows through Belgrade, the capital of Serbia, and is a defining feature of the city's geography. Belgrade sits at the confluence of the Danube and Sava rivers, making it strategically important throughout history. The Spree flows through Berlin, while 'Dimbovitya' appears to be a misspelling of the Dâmbovița River in Romania.

The Tigris River flows through Baghdad, the capital of Iraq, and is one of the two great rivers that define Mesopotamia (the 'land between two rivers'). The Tigris runs approximately 1,850 kilometers through Turkey and Iraq before joining the Euphrates. The Scheldt flows through Belgium/Netherlands, the Amset appears fictional, and the Nile is in Africa.