[单项选择]

Your eye is a window on the nerves and blood vessels, revealing vital information about your entire body. An (1) exam starts from the outside and works in. First the ophthalmologist (眼科医生) gauges (2) with the familiar wall chart and checks visual field by moving objects in and out of (3) . A limited visual field could be the (4) of the high inner eye pressure of glaucoma(青光眼)or (5) a tumor pressing on nerves leading from the eye. The physician also checks for infection around the lashes and notes how fast the lids follow the eyes downward. Lid lag sometimes (6) thyroid disease (甲状腺疾病).
If one pupil contracts (7) the other doesn’t, the physician is (8) to the fact that (9) a tumor or stroke, perhaps, has damaged the nerves between the eye and brain. A tumor as far away (10) the lung can cause capillary problems by hitting a nerve that loops through the neck.
The white of the eye, tear ducts
A. signs
B. signals
C. gestures
D. symbols