Dawki Or Umngot River Meghalaya

Popularly known as Dawki river, the Umngot river in Meghalaya is undisputedly the cleanest river in Asia with its crystal clear water. It originates from the Eastern Shillong Peak, which is located 1,800 m above sea level.

The river is in the village of Mawlynnong ("God's Own Garden") in Meghalaya, close to India’s border with Bangladesh, which is touted as Asia’s Cleanest Village.

Alongside cleanliness, the village has also achieved a rare feat — a 100% literacy rate.

It acts as a natural divide between Jaintia and Khasi hills, before finally flowing into Bangladesh.

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Bonn Convention: The Convention on the Conservation of Migratory Species of Wild Animals, also known as the Convention on Migratory Species (CMS) or the Bonn Convention, is an international agreement that aims to conserve migratory species within their migratory ranges. India is a signatory to this Convention.

Answer & Explanation
c) both (a) and (b). 
The Arabian Sea branch of the monsoon is much more powerful than the Bay of Bengal branch because – 1. Arabian sea is larger than the Bay of Bengal and 2. entire Arabian sea current advances towards India, whereas only a part of the Bay of Bengal current enters India.
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