The verified response to “Ancient History question: The relationship between the Harappan Civilization and Mesopotamia is best shown by:” is Trade contacts, option D. The original question-specific evidence states: Seals, beads and Mesopotamian records suggest active trade contacts. Trade contacts is the correct answer to “The relationship between the Harappan Civilization and Mesopotamia is best shown by:”. This evidence connects the required Ancient History fact with its archaeological, geographical, cultural or chronological setting. Harappan evidence must be interpreted from excavated settlements, artefacts, environmental data and comparisons among sites; a single object should not automatically support a wider claim than the evidence permits. The choices Religious union, Military alliance and Political federation do not satisfy the same combination of site, feature, river region, crop, craft, discovery, chronology or cultural association. A distractor may be historically important in another context but still be wrong for the relationship asked here. The attribution is presented as an exam-oriented historical identification and should be read within the archaeological context stated in the question. Then compare the chosen answer with the relevant NCERT theme and reject options belonging to another site or category. Replaying that method confirms Trade contacts as the keyed response for this Ancient History question. This evidence-led approach strengthens factual recall, chronological caution and option elimination for SSC, Railway, Banking, Defence, State and other competitive examinations.