Final answer:
The verb form that best fits the blank is 'leyó'.
Step-by-step explanation:
The form of the verb leer that best fits the blank in the sentence is option C, leyó. This is the preterite tense of the verb, which is used to indicate an action that happened in the past and is completed. In this case, the sentence is talking about reading a story that happened yesterday, so the preterite tense is appropriate.
Learn more about verb conjugation