Answer: The correct answer is 1- Vieron, 2- Vio & 3- Vimos.
1- Ellos vieron el tomate.
2- Él vio las frutas y los vegetales.
3- Nosotros vimos la sandía.
Those are the correct or appropriate form of the verb Ver in each sentence.
The first one is "Vieron", the second one is "Vió" and the third one is "Vimos".
