human
Question: The air here is fresh. There are not many tall buildings in our town. The best building is in our school. There are four hundred students and twenty-five teachers in our school. In the front of the school, there is a playground. I often play basketball with my classmates on it. There is a little garden behind our school. And we can grow beautiful flowers and plant trees in the garden. Next the garden, there is an orange orchard . You can hear birds singing everywhere. There is a river not far from our school. In summer, we usually go swimming in it. People can hear   _   singing here and there.

Choices:
A) students
B) birds
C) cows
D) teachers
gpt
The correct answer is 1: birds.