<u>Right answer:</u>
<h2>Lee</h2>
This is a conversation between two people, in which A asks to B <u>what is he or she reading.
</u>
Now, in Spanish, if you want to talk to a person in an <u>educated and formal way</u>, you should use <em>Usted</em> (abbreviated <em>Ud.</em>) instead of <em>Tú</em> (you).
Here, person A is making the question in a polite mode to person B using <em>Usted</em> (you).
In addition,<u> in Spanish grammar</u>, <u>the verbs must be conjugated in accordance with the subject</u>. In this case the verb<em> </em><em>leer </em>(to read) in present tense is conjugated with the 2nd person in singular (formal) as:
(Usted) lee
Then, the conversation is:
<h2>
A: ¿Qué<u>
lee</u>
Ud.? </h2><h2>
B: Una novela de Isabel Allende. </h2>
A: What do you read?
B: A novel written by Isabel Allende.
The option (Tú) lees (you read) is incorrect because is informal; and the options cree (believes, 3rd person singular) and crees (believe) do not match with the context of the conversation