The question asks which river among the given options does not cross international borders. Let's analyze each option to determine this:
- Ganga: Originates in India and flows into Bangladesh, thus crossing international borders.
- Brahmaputra: Originates in Tibet, flows through India, and then into Bangladesh, making it an international river.
- Ravi: Originates in India and flows into Pakistan, therefore, it crosses international borders.
- Tapi: Entirely located within India, it does not cross any international borders.
- Teesta: Flows from India into Bangladesh, hence it crosses international borders.
After evaluating these options, we can conclude that the Tapi river is the one which does not cross international borders.