What is the most populous Muslim-majority nation in 2010?

The answer is Indonesia because it has the largest population of Muslims in the world. With over 200 million Muslims, constituting approximately 88% of its population, Indonesia has the highest number of Muslims among any other country. This can be attributed to the fact that Indonesia has a larger overall population compared to other Muslim-majority nations, such as Pakistan or Bangladesh, which makes it the most populous Muslim-majority nation. Additionally, Islam has a long history in Indonesia, having been introduced to the archipelago centuries ago, contributing to its significant Muslim population.