Per the HTML5 specification, if a element meets the following criteria:
Required attribute is specified
Multiple attribute is not specified
Display size is 1 (SIZE=2 or more is not present)
First option has an empty value (e.g., value="")
First option is a direct child of the element (not within an
Then, the first option becomes the placeholder label option. By leaving the initial value blank, the element is forced to have a default value to submit, thus enforcing the required attribute.
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