The correct answer is Option 3: Johannesburg.

The World Summit on Sustainable Development, also known as Rio + 10, was held in Johannesburg, South Africa. The summit took place from August 26 to September 4, 2002. It was an international event organized by the United Nations to address key global environmental and developmental issues, following up on the original Earth Summit held in Rio de Janeiro, Brazil, in 1992.

Here`s some additional information to support this answer:

1. Historical Context: The World Summit on Sustainable Development was a milestone event marking ten years since the original Earth Summit in Rio de Janeiro. As such, it aimed to review progress made since then and discuss new strategies for sustainable development.

2. Geographical Consideration: Johannesburg, the largest city in South Africa, was chosen as the host city for the summit. It was a symbolic choice as the country had experienced significant political changes, transitioning from apartheid to democracy. South Africa`s commitment to sustainable development made it a fitting location for the event.

3. Global Attendance: The summit brought together an extensive gathering of world leaders, policymakers, representatives from non-governmental organizations (NGOs), and other stakeholders. The international community converged in Johannesburg to engage in discussions and negotiate agreements on various environmental, social, and economic issues.

4. Outcomes and Agreements: The Johannesburg Summit produced several important documents and agreements. The primary outcome was the adoption of the Johannesburg Declaration on Sustainable Development, which reaffirmed global commitment to sustainable development and outlined key priorities and strategies. Additionally, the summit resulted in the Johannesburg Plan of Implementation, a comprehensive blueprint for implementing sustainable development goals and targets.

In summary, the World Summit on Sustainable Development (Rio + 10) was held in Johannesburg, South Africa, to review progress made since the original Earth Summit and discuss new strategies for sustainable development. The choice of Johannesburg as the host city reflected the country`s commitment to sustainable development and marked an important moment in global efforts to address environmental and developmental challenges.