The headquarters of the Food and Agriculture Organisation (FAO) of the United Nations are located in which city?

Introduction / Context:
The Food and Agriculture Organisation, commonly known as FAO, is a specialised agency of the United Nations which fights hunger and works to improve agriculture, forestry and fisheries worldwide. Questions about the headquarters of major UN agencies are common in general knowledge exams, and FAO is one of the most frequently asked organisations.

Given Data / Assumptions:

• The question identifies FAO as a UN body concerned with food and agriculture.
• We are given five possible host cities: Sofia, Rome, Havana, London and Geneva.
• We assume knowledge of the major UN headquarters and which agencies are based in each city.
• Exactly one city correctly hosts the headquarters of FAO.

Concept / Approach:
FAO headquarters have been located in Rome, Italy, since shortly after the Second World War. Italy offered facilities in Rome and the organisation moved its main offices there. While Geneva and New York are important UN centres, and London is a major global city, FAO is specifically associated with Rome. The approach is to match the agency with the correct city using memory and elimination of unlikely choices.

Step-by-Step Solution:
Step 1: Recall that FAO is often mentioned together with the city of Rome in official documents and news reports, indicating where its headquarters are situated. Step 2: Consider Geneva and London. These cities host many international bodies, but FAO is not headquartered there. Geneva is more linked to WHO and other agencies, while London is not a main UN headquarters city. Step 3: Sofia and Havana are national capitals of Bulgaria and Cuba respectively, but they are not known as FAO headquarters. Step 4: Process of elimination and factual knowledge both point to Rome as the correct city.

Verification / Alternative check:
To verify, think of the cluster of Rome based UN agencies that work on food and agriculture, including FAO, the International Fund for Agricultural Development and the World Food Programme. This strong association of Rome with food security confirms that FAO headquarters are in Rome. Official UN and FAO websites clearly state Rome as the host city.

Why Other Options Are Wrong:
Option A, Sofia, is wrong because it does not host any major UN specialised agency headquarters.

Option C, Havana, is wrong since Cuba hosts regional offices for some agencies but not the global headquarters of FAO.

Option D, London, is wrong because although it is influential in world affairs, it is not designated as the headquarters of any of the main UN specialised agencies.

Option E, Geneva, is wrong in this context because even though Geneva is a major UN hub, FAO is not based there; instead, bodies like WHO and UNHCR are located in Geneva.

Common Pitfalls:
A frequent mistake is to assume that because Geneva is known for many UN agencies, any unfamiliar agency must also be located there. Another error is to confuse FAO with agencies like WHO or UNHCR, which actually are based in Geneva. To avoid these confusions, remember the simple association: food, agriculture and hunger related agencies are strongly linked with Rome.

Final Answer:
The headquarters of the Food and Agriculture Organisation are located in Rome.