The correct answer is option 2: Ganga. The river known as Padma in Bangladesh is actually a part of the larger Ganges River system. The Ganges River, also known as the Ganga, originates in the Himalayas and flows through several countries including India and Bangladesh. In Bangladesh, the Ganges River splits into two major distributaries, the Padma and the Jamuna. The Padma River is the main distributary and it continues to flow southwards through Bangladesh until it merges with the Meghna River and eventually reaches the Bay of Bengal. Therefore, although the river is known as Padma in Bangladesh, its actual name is the Ganges or Ganga.