Of the American dialects Southern dialect is closest to British English?

That's a common misconception, but it's not entirely accurate. While Southern American English shares some features with British English, it's more accurate to say it's closer to certain British dialects than to British English as a whole.

Here's why:

* Shared features: Both Southern American English and certain British dialects (particularly those from the south of England) share features like the use of "y'all" (although pronounced differently), the use of "ain't," and some vowel pronunciations.

* Different influences: Southern American English was heavily influenced by early settlers from England, particularly those from the South. However, it has also been shaped by other influences, such as African American Vernacular English and Native American languages.

* Divergence over time: American English, including its Southern dialect, has diverged significantly from British English over the centuries due to separate developments in vocabulary, grammar, and pronunciation.

To summarize, while some aspects of Southern American English may seem closer to certain British dialects, it's important to remember the complex history and evolution of both languages. Both have developed unique features and are distinct from each other.