Tunnel vision means a person has difficulty seeing things ... A. in the upper range of their field of vision.
B. on the edges of their field of vision.
C. through the center of their field of vision.

B.

Explanation:

Tunnel vision is the loss of peripheral vision, or edges of your sight. They call it "tunnel vision" because it looks like you are looking through a tunnel, as you have no peripheral vision.

C. through the center of their field of vision.

Explanation:

You can see well when staring straight ahead, but it seems as though you're looking at things through a narrow tube.

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