Cortan because ellos means they and they is plural. Corta would be for ella/el/usted
I did it but It won’t let me paste it here so It will be in the comments
EstudianteA: Acabo de limpiar el baño porque si miras el baño ves que está brillante y limpio
(he finished cleaning the bathroom because if u look at the bathroom you see that its shiny and clean)
This is true bc if u look at the bathroom it is very clean and if u look at the plants they look like the haven’t been touched (Esto es cierto porque si miras el baño, está muy limpio y si miras las plantas, parece que no las han tocado.) so Estudiante B (Student B) is wrong (esta mal) hope this helps
