Which community was founded by Alexander Milne on Lake Pontchartrain?

Milneberg is the correct choice because it was indeed established by Alexander Milne on the shore of Lake Pontchartrain. This community became popular in the late 19th century as a resort destination for residents of New Orleans, taking advantage of the scenic beauty and recreational opportunities afforded by the lake. Milneberg was characterized by its waterfront attractions, which made it a fashionable getaway during that era.

The other options do not pertain to the founding by Alexander Milne. Basin Street, for instance, is known for its historical significance related to the jazz culture and the vibrant nightlife of New Orleans but was not founded by Milne. City Park is a major public park in New Orleans with different historical roots and development timelines. Gov Nichols Street also does not have any direct connection to Milne's founding of a community on Lake Pontchartrain.