Answer: The verb form that correctly completes this sentence is "debes".
Explanation: <u>The verb that fills in the blank must be conjugated in the second person because the pronoun "tú" indicates second person.</u> <u>In Spanish, the second person in verbs is usually signaled by an "-s" at the end of the verb</u>. In that way, <u>the second person verb</u> among the options provided<u> is "debes"; </u>therefore, "debes" is the verb form that fills in the blank. In contrast, "debe" is used for third person, "debo" for first person singular, and "debemos" is used for first person plural.