The verb that's spelled correctly in the preterit tense is:
<u><em>Subieron</em></u>.
Explanation:
In Spanish, two types of past tense can be found: Simple Preterite and Imperfect Preterite, since the Simple Preterite is the most used and applicable for the exercise, we will focus on it. The conjugation of the verb <em>"subir"</em> in Simple Preterite is shown below:
<em>Yo </em><em>subí</em><em>.</em>
<em>Tú </em><em>subiste</em><em>.</em>
<em>Él </em><em>subió</em><em>.</em>
<em>Ella </em><em>subió</em><em>.</em>
<em>Ello </em><em>subió</em><em>.</em>
<em>Nosotros </em><em>subimos</em><em>.</em>
<em>Ellos </em><em><u>subieron</u></em><em>.</em>
As you can see, <u><em>"subieron"</em></u> is an applicable conjugation for the second person in the personal pronoun <em>"ellos,"</em> as well as it can be identified that the other options provided do not apply within any personal pronoun, in fact, <em>"subaron"</em> does not exist and <em>"subo"</em> is not found in the Past but in Present.
