At the Aquarium by Max Eastman

Serene the silver fishes glide,
Stern-lipped, and pale, and wonder-eyed!
As through the aged deeps of ocean,
They glide with wan and wavy motion.
They have no pathway where they go,
They flow like water to and fro,
They watch with never-winking eyes,
They watch with staring, cold surprise,
The level people in the air,
The people peering, peering there:
Who wander also to and fro,
And know not why or where they go,
Yet have a wonder in their eyes,
Sometimes a pale and cold surprise.

One theme of the poem is
A. fish in aquariums enjoy looking at the people.
B. aquariums are jails for fish and should not exist.
C. people and animals are not so different after all.
D. people should accept people for who they are.