The word “that” in line 10 refers to
A. foveae
B. areas of the eye
C. cones
D. visual distinctions
According to the passage, why might birds and animals consider humans very visually handicapped?
A. humans can’t see very well in either air or water
B. human eyes are not as well suited to our needs
C. the main outstanding feature of human eyes is color vision
D. human eyes can’t do what their eyes can do
The phrase “without a hitch” in line 2 is closest in meaning to
A. unaided
B. without glasses
C. with little hesitation
D. easily
The word “criterion” in line 1 is closest in meaning to
A. standard
B. need
C. expectation
D. rule
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