The correct answer is (d). Global climatic change.
The Bali Summit was the 13th Conference of the Parties (COP 13) to the United Nations Framework Convention on Climate Change (UNFCCC). It was held in Bali, Indonesia, from 3 to 15 December 2007. The main theme of the summit was to find a way to reduce greenhouse gas emissions in order to prevent dangerous climate change.
The summit was attended by representatives from 192 countries. The negotiations were difficult, but in the end, the parties agreed to a roadmap for future negotiations. This roadmap, known as the Bali Action Plan, set out a number of steps that countries would need to take in order to reduce greenhouse gas emissions.
The Bali Action Plan was a significant achievement, but it was only a first step. The real challenge will be to implement the plan and to achieve the necessary reductions in greenhouse gas emissions.
The other options are incorrect because they were not the main theme of the Bali Summit.
(a) International trade is a major issue, but it was not the main focus of the Bali Summit.
(b) International terrorism is a serious problem, but it was not the main focus of the Bali Summit.
(c) Global pollution is a major issue, but it was not the main focus of the Bali Summit.