A. The later Vedic Age/they are purported to be records of sages who conveyed their spiritual insights to students.
Explanation:
Upanishads were early also known as Vedanta meaning at the end of Vedas. they contain the changing philosophical notions of that time. The influence of Buddhism, Jainism, and concepts of early Hinduism can be noticed in it. They contain transitional ideas from Vedic rituals to new spiritual ideas. The idea of atman(individual soul) and brahman(universal soul) were first appeared in Upanishads.
