The headquarters of the Organisation of Petroleum Exporting Countries (OPEC) is in

Step 1: Analyze the question The question asks where OPEC's headquarters is located.

Step 2: Explain the concept OPEC (Organisation of Petroleum Exporting Countries) was founded in 1960 in Baghdad, Iraq. Its first headquarters was in Geneva, Switzerland, then it moved to Vienna, Austria in 1965. Nigeria joined in 1971. OPEC coordinates the petroleum policies of its member countries, for example by influencing oil output and prices.

Step 3: Work through the options

• A. Lagos: Nigeria is a member, but the headquarters is not here.
• B. Moscow: Russia is not an OPEC member (it works with OPEC+ but is not part of OPEC itself).
• C. Paris: This is the base of the International Energy Agency (IEA), not OPEC.
• D. Vienna: Correct. OPEC's secretariat has been in Vienna, Austria since 1965.
• E. Washington: This is the base of the IMF and World Bank, not OPEC.

Step 4: Answer The correct answer is D. Vienna.

Exam tip: Link organisations to their cities with a short list:

• OPEC → Vienna
• UN → New York
• WTO, WHO, ILO → Geneva
• ECOWAS → Abuja
• AU → Addis Ababa
• IMF/World Bank → Washington, D.C.