With reference to ancient India (600-322 BC), consider the following pairs :
| Territorial region |
River flowing in the region |
| I. Asmaka |
Godavari |
| II. Kamboja |
Vipas |
| III. Avanti |
Mahanadi |
| IV. Kosala |
Sarayu |
How many of the pairs given above are correctly matched?