Under Articles 31-32 VCLT, treaty INTERPRETATION shall be:

1. Article 31(1) VCLT: 'A treaty shall be interpreted in good faith in accordance with the ordinary meaning to be given to the terms of the treaty in their context and in the light of its object and purpose.' 2. Article 31(2)-(4) define 'context' (text + preamble + annexes + agreements concluded between parties in connection with treaty + subsequent agreements + subsequent practice + relevant rules of international law). 3. Article 32 permits recourse to 'SUPPLEMENTARY MEANS OF INTERPRETATION' including PREPARATORY WORK (travaux préparatoires) and circumstances of conclusion — when needed to confirm meaning under Article 31 OR to determine meaning when Article 31 leaves meaning ambiguous, obscure, manifestly absurd or unreasonable. 4. Articles 31-32 reflect customary international law. 5. Hence option B is correct. _Source: UN Charter 1945 / Vienna Convention on Law of Treaties 1969 / ICJ Statute / ARSIWA 2001 — Vienna Convention on the Law of Treaties 1969, Articles 31-32_