Final answer:
The correct verb form for ellos (sentir) is sintieron.
Step-by-step explanation:
The correct verb form for ellos (sentir) is sintieron. This is the third person plural preterite form of the verb sentir, which means 'to feel' in English. In this form, the verb is conjugated to match the subject 'ellos', which means 'they' in English.
Learn more about Spanish verb conjugation