This question concerns the use of <em>conocer</em> v. <em>saber, </em>both infinitives meaning "to know."
The difference: <em>Saber</em> is used to speak about known facts, while <em>conocer</em> is used to speak of familiar things.
<u>Examples</u>
<em>Saber</em>
I know where it is.
<em>Yo </em><em>sé</em><em> donde est</em>á.
<em>Conocer</em>
She knows him.
<em>Ella lo </em><em>conoce</em>.
<u>The sentence in question</u>
<em>Tengo mucha hambre. ¿________ usted un buen restaurante italiano?
</em>
Translation:
I am very hungry. Do you [blank] a good Italian restaurant?
The person is asking if someone knows - or if they are familiar with - a good Italian restaurant. We know we will be using a conjugation of <em>conocer</em>, and not <em>saber</em>. That leaves two options: <em>conoces</em> and <em>conoce</em>. The correct conjugation depends on the subject. Our subject is <em>usted</em>, the formal "you" in Spanish. The correct conjugation is <em>conoce</em><em>, </em>as <em>conoces</em> is the conjugation for the informal "you" (<em>tú conoces</em>).
<h3>
Answer:</h3>
d) <em>conoce
</em>