I feel like it could be 3rd or 4th but 3rd seems more convincing
Ya tengo el regalo perfecto para mi hermana. Lo compré en el mercardo de artesanías
Tú ERES inteligente.
Usted ES estudiante de la escuela.
Ana, y María SON altas.
Tomás, Estela y yo SOMOS hermanos.
Los estudiantes SON amigos.
Ustedes SON de California.
Nosotros SOMOS doctores.
4th one. Carmen caminaba a la playa.
The first one is using the nosotros form. The second one is using preterite but using the yo form. The third is using the you form.
The 4th one is saying it was a continuos activity and it was talking about a specific person.
34 is the answer. And if needed the next one would be 19.