The headquarter of the Organization Of Petroleum Exporting Countries (OPEC) is in

Analyze the question: The question asks where OPEC's headquarters is located. This is a factual recall question, common in the Economics section on international organizations.

Explain the concept: OPEC was founded in 1960 in Baghdad, Iraq. Its first headquarters was in Geneva, Switzerland (1960 to 1965). The headquarters then moved to Vienna, Austria in 1965, and it has remained there ever since. Nigeria joined OPEC in 1971, but Lagos has never been the headquarters.

Solution, option by option:

• A. Paris, France: Paris hosts the OECD and UNESCO, not OPEC.
• B. Geneva, Switzerland: This was OPEC's first base, but it moved away in 1965. It is the trap option.
• C. Lagos, Nigeria: Nigeria is a member, not the host.
• D. Vienna, Austria: This is the current and long-standing headquarters.

Answer: The correct option is **D.

Tip: Link the two V's: Vienna = OPEC's home, and remember that Geneva was only the "starter" location. For other organizations, remember that Paris hosts the OECD, and Geneva hosts the WTO and WHO.