With reference to the Himalayan rivers joining the Ganga downstream of Prayagra from West to East, which one of the following sequences is correct?
* Gomati: The Gomti River originates in the Central Himalayas and joins the Ganga near Varanasi, Uttar Pradesh. * Ghaghara: The Ghaghara River, also known as the Ghagra-Rapti River, is the largest tributary of the Ganga. It originates in the Nepal Himalayas and joins the Ganga near Chhapra, Bihar. * Gandak: The Gandak River originates in the Nepal Himalayas and joins the Ganga near Patna, Bihar. * Kosi: The Kosi River, also known as the Koshi River, is known for its erratic behaviour and floods. It originates in the Nepal Himalayas and joins the Ganga near Katihar, Bihar. Therefore, the correct sequence is Gomati - Ghaghara - Gandak - Kosi.