permalink in query

how do I add links to the post in the loop?

<?php

// The Query
$the_query = new WP_Query( 'category_name=Pizza' );

// The Loop
while ( $the_query->have_posts() ) : $the_query->the_post();
	echo '<li>';
	echo the_title();
	echo '<br>';
	echo the_post_thumbnail('thumbnail');
	echo '</li>';
endwhile;

// Reset Post Data
wp_reset_postdata();

?>