This leading garment making country has one of the highest population densities in the world, and is subject to massive flooding brought on by monsoon winds during the wet season O Turkmenistan
O Singapore
O Taiwan
O Bangladesh

Bangladesh is the country in question.

Explanation:

Bangladesh is a country that is located in the northeastern part of the historical region of India, nowadays referred to as the Indian subcontinent. This country is among the mainland countries that have the lowest elevation in the world. It is also located in an area where it is heavily impacted by the monsoons.

While the wet monsoons can be seen as something positive as they provide water for the rest of the year for humans, animals, and plants, in Bangladesh, they also have a very negative effect. The country is at a low stage of development, so its infrastructure is bad and there isn't any particular infrastructure that will protect the population from the enormous amounts of water. This results in high-scale flooding of the southern part of the country, with most of the population having to live without basic means for life and having their lives at stake.