The author’s purpose in writing the passage lies in ___.
A. showing that we sometimes are deceived by our own eyes.
B. informing us about the different functions of the eye organs.
C. regretting that we are too slow in the study of eyes.
D. marveling at the great work done by the retina.
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The purpose of a healing ceremony lies in ___.
A. pleasing the ghosts
B. attracting supernatural powers
C. attracting the ghosts
D. creating a sandpainting
Twenty-four still photographs are made into a continuous moving picture just because ___.
A. the image we see usually stays longer than it actually appears.
B. we see an object in comparison with its surroundings.
C. the eyes catch million pieces of information continuously.
D. rods and cones send messages 20 to 25 times a second.
You stare at waterfall for a minute or two, and then shift your gaze to its surroundings.
A. matched to six to seven million structures called cones.
B. confused in the body’s sensors of both rods and cones.
C. interpreted in the brain as what must be the case.
D. signaled by about 120 million rods in the eye.
The visual sensor that is capable of distinguishing shades of color is called ___.
A. cones
B. color vision
C. rods
D. spectrum
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