The correct answer is option 2 - Jhelum. The river Jhelum was earlier known as "Vitasta". To understand the options better, let`s look at each one:

Option 1 - Tista: Tista is a river that flows through India and Bangladesh, but it was not known as "Vitasta" in the past.

Option 2 - Jhelum: This is the correct answer. The Jhelum river, which flows through India and Pakistan, was originally called "Vitasta".

Option 3 - Tungabhadra: The Tungabhadra is a river in India, but it was not known as "Vitasta" in the past.

Option 4 - Bharatpuzha: Bharatpuzha, also known as the Nila river, is a river in Kerala, India. However, it was not known as "Vitasta" in the past.

Therefore, the correct answer is option 2 - Jhelum. It was previously known as "Vitasta".