<?php echo ($signi== 'Yes') ? "checked" : "" ; ?>
<!DOCTYPE html>
<html>
<head>
<title></title>
</head>
<body>
<h1>Pizza</h1>
<form method="POST" action="pizza.php">
Wat op pizza:<br>
<input type="radio" value="Pepperoni" name="type">Pepperoni<br>
<input type="radio" value="Ananas" name="type">Ananas<br>
<input type="radio" value="Ansjovis" name="type">Ansjovis<br>
<input type="radio" value="Broccoli" name="type">Broccoli<br><br>
<input type="submit" name="Bestellen" value="Bestellen"><br>
</form>
</body>
</html>