The compilation of which among the following is based upon the Rig Veda?

Which one of the following is oldest Veda :

Which of the following Rig-Vedic Gods is not mentioned in 'Boghazkoi' inscription?

Which of the following is a characteristic of Mandala IX of the Rigveda?

Which of the following Gods is referred to as 'Ritasya Gopa' in the Rigveda?

Who among the following was a Brahmavadini who composed some hymns of the Vedas?