Two or more form submit buttons value.

Two or more form submit buttons value.

I am troubled by proper use of two or more form submit buttons.

<form action="index.php" method="post">
    <button type="submit" name="Options" value="Option1">Option1</button>
    <button type="submit" name="Options" value="Option2">Option2</button>
    <button type="submit" name="Options" value="Option3">Option3</button>
</form>

The following results are obtained when requests by pushing a "Option1" button by the usual html.

$_POST -> { ["Options"]=> string(7) "Option1" }

However, when jQuery Mobile is used, a required value is not acquired even if submit is performed.

How is a required value acquired if it carries out?