The correct option is D All of the above.
It is generally believed that Malayalam has evolved from Tamil. Sanskrit also has greatly influenced the development of Malayalam. Vattezhuthu and Kolezhuthu were the scripts used to write old Malayalam.
Krishnagatha by Cherussery, Adhyatma Ramayanam Kilippattu and Mahabharatham Kilippattu by Ezhuthachan, Thullal literature of Kunchan Nambiar, etc. contributed to the development of the Malayalam language.