Step 1: Concept
Swaramela Kalanidhi is a monumental 16th-century Sanskrit musicological treatise written around 1550 AD that laid the early conceptual foundations for the modern Carnatic music system.
Step 2: Author Identification
The text was authored by the scholar-musician Ramamathya, who served as a court musician in the Vijayanagara Empire.
Step 3: Historical Impact
Swaramela Kalanidhi is historically significant because it was the first work to systematically introduce the concept of Mela (parent scales) and Raga (derived scales) classification, describing 20 basic melas. It directly bridged the gap between ancient medieval musicology and the modern 72-Melakarta scheme.
Step 4: Conclusion
Among the options provided, Ramamathya is the author of Swaramela Kalanidhi, matching option (C).
Final Answer: (C)