在下面的文字中强调“metropolitan”这个词。
<h1>Tokyo</h1>
<p>
Tokyo is the capital of Japan,
the most populous @(4)metropolitan@(5)
area in the world.
</p>
<h1>Tokyo</h1>
<p>
Tokyo is the capital of Japan,
the most populous <em>metropolitan</em>
area in the world.
</p>