Consider the following statements:

I. It rises in the Pulachimalai Hills of the Western Ghats.

II. It is the third-longest river in Kerala.

III. It is popularly referred to as the 'Dakshina Bhageerathi' due to its association with the Sabarimala temple.

IV. The silt deposited by this river and its tributaries has helped form the fertile Kuttanad region, known as the 'rice bowl of Kerala.'

The river described above is: