Answer: prefieren; prefieres
Explanation: We must complete two blanks, the conversation is:
—Roberta, ¿les gustaría a tus hijos cenar con nosotros el sábado?
—¡Claro que sí! Mis hijos ________cenar. Tienen que competir en la mañana.
—Bien. Y tú, Roberta, ¿________ carne o pescado para cenar?
—Pescado.
A rough translation of the conversation would be:
-Roberta, your sons would like to diner with us next Saturday?
- Shure! My kids_____ dinner (here may be a word missing, but it does not matter), they must compete in the morning.
-Nice. And you, Roberta, do you ____ meat or fish for dinner?
-Fish
Where the blanks are completed by conjugations of the verb "preferir"
Here the first blank is for the kids, that is more than one, so we must use the plural, and in this case, we are also using "Ellos", so the correct conjugation would be "Ellos prefieren"
For the second blank, the speaker is asking to Roberta what she prefers, so the subject is one, and in this case, the person is "Tú", so the correct conjugation is: "Tú prefieres"
Then the right answer is the third option:
prefieren; prefieres
—Roberta, ¿les gustaría a tus hijos cenar con nosotros el sábado?
—¡Claro que sí! Mis hijos prefieren cenar. Tienen que competir en la mañana.
—Bien. Y tú, Roberta, ¿prefieres carne o pescado para cenar?
—Pescado.
