Of the 5 nations on this chart, which has the greatest ethnic diversity

Without a specific chart provided in the question, I'm unable to determine the specific nations under consideration. However, based on general knowledge, a possible answer could depend on the nations considered in the chart. Here is a list of five countries that are often regarded as ethnically diverse:

1. Brazil: Known for its significant blend of Indigenous, European, African, and Asian ancestries, Brazil stands out as one of the most ethnically diverse nations worldwide.

2. United States: With its strong history of immigration, the United States comprises diverse ethnic groups, including European, African, Latino, Asian, and Indigenous populations.

3. Canada: Canada is also known for its multiculturalism and ethnic diversity, with various groups such as European, Asian, African, Middle Eastern, and Indigenous communities.

4. Australia: Home to a multicultural society, Australia exhibits a wide range of ethnic backgrounds, including European, Asian, Indigenous, and Middle Eastern communities.

5. South Africa: Notable for its substantial mix of ethnicities, South Africa encompasses diverse groups, including Black African, White, Colored, Indian, and various other ethnic communities.

Please note that this list is based on general knowledge and perception and might not correspond to a specific chart or dataset.