The correct option is C Rigveda
The early Vedic literature was also called the ‘Sruti Literature’, meaning ‘what is heard’. Among these are the four most revered Vedas- the Rigveda, the Samaveda, the Yajurveda, and the Atharvaveda. The Rigveda is the oldest and believed to be composed during the early 1500 BCE. It contains 1028 hymns or mantras that are divided into ten mandalas. They were written in praise of various gods and were intended to be used for invoking the deities and seeking their support. One of these hymns is the Gayatri Mantra.