In this question, we are asked to identify the odd one out among the given options.

Option 1 - Samveda: It is one of the four sacred texts of Hinduism known as Vedas.

Option 2 - Yajurveda: It is another one of the four Vedas and contains hymns and rituals for worship.

Option 3 - Vishnu Purana: This is a Hindu scripture that describes the history and genealogy of Vishnu and his avatars. It is different from the Vedas.

Option 4 - Rigveda: This is the oldest and most ancient of the four Vedas, containing hymns and prayers.

From the given options, option 3 (Vishnu Purana) is the odd one out as it is a scripture that describes the stories of a deity, while the other options are all related to the Vedas.