Which statement displays the output as 54321.00?

To display the output as 54321.00, the correct statement is the one that utilizes the correct formatting specifier, which is a format string designed for floating-point numbers.

In the chosen statement, the format specifier %8.2f accomplishes the desired result by indicating a total minimum width of 8 characters, with 2 digits following the decimal point. This means the output will right-align the number within a width of 8 characters and will include two decimal places, ensuring that the number is displayed as "54321.00".

The first part %8 specifies the total width, which helps in aligning the output. The .2 specifies that two digits should be shown after the decimal, resulting in the ".00". The f at the end denotes that we are dealing with a floating-point number. Therefore, the format will produce the correct output, including adequate padding if necessary, ensuring it adheres to the specified format.

The other options contain formatting mistakes. For instance, commas in format specifiers do not function correctly in Java’s printf method syntax. The presence of these inaccuracies in those statements would prevent them from displaying the desired output correctly.