Explanation:

2nd option is correct.
Theory of classical music is discussed in Samaveda.
The Samaveda (saman "song" and veda "knowledge"), is the Veda of melodies and chants. It is an ancient Vedic Sanskrit text, and part of the scriptures of Hinduism. One of the four Vedas, it is a liturgical text whose 1,875 verses are primary derived from the Rigveda.