Given the task definition and input, reply with output. You will be given a trivia clue, and the category it belongs to. You should answer with the best answer that belongs in the category and is described by the clue. For simplicity, answers should be in all lower cased letters.

Category: THE STOCK EXCHANGE 
Clue: With over 20,000 stores worldwide, it began trading on the NYSE in July 2000 under the symbol SE

7-eleven