The correct chronological sequence is: Early Vedic Tradition (C) around 1500 BCE, followed by the Early Upanishads (B) around 800 BCE. The First Stupa (A) was built during the 3rd century BCE under Ashoka. Earliest Trade (E) dates back to the Harappan Civilization (approximately 2500 BCE), and Mahayana Buddhism (D) developed in the 1st century CE.