Correct Option
The correct option is 1, 2, 3 and 4.
Explanation
The Upanishads constitute the philosophical culmination of the Vedic corpus and focus on metaphysical questions concerning reality, self, and ultimate truth.
Statement-wise Analysis
- Statement 1: Correct. The Upanishads are classified as later Vedic texts and form the concluding part of the Vedas.
- Statement 2: Correct. Upanishadic teachings are frequently conveyed through dialogues between teachers and students, using simple conversational formats to explain abstract ideas.
- Statement 3: Correct. Shankaracharya extensively developed and systematised the philosophical ideas of the Upanishads through his Advaita Vedanta doctrine.
Key Takeaway: The Upanishads are later Vedic philosophical texts that employ dialogue-based exposition and were foundational to later Indian philosophical traditions such as Advaita Vedanta.