Final answer:
The correct form of the verb 'viajar' in the sentence 'Juan has traveled a lot' is 'ha viajado.'
Explanation:
The correct form of the verb viajar in the given sentence 'Juan has traveled a lot' is option C) ha viajado. This form uses the present perfect tense in Spanish to indicate an action that started in the past and continues into the present or has just been completed. For example, 'Juan ha viajado por Europa muchas veces' (Juan has traveled through Europe many times).
Learn more about Spanish verb conjugation here:
https://brainly.com/question/29637806
