阅读短文，根据短文内容，从短文后的选项中选出能填入空白处的最佳选项。选项中有一项为多余选项。
Spending two or three hours playing outdoors each day can reduce a child's chance of becoming
short-sighted, a research shows. _____
The Australian government researchers believe that the sunlight is good for people's eyes. They compared
the vision (视力) and habits of 100 seven-year-old children in Singapore and Australia. In all, 30% of the
Singaporean children were short-sighted - this rate (比率) was ten times higher than Australian children.
_____ However, the Australia children spent an average (平均) of two hours a day outdoors — 90 minutes
more than the Singaporean children.
Professor (教授) Ian Morgan said, "Humans are naturally long-sighted.____ We're also seeing more and
more short-sighted children in cities all around the world- and the main reason may be that city children spend
less time outdoors."
Daylight can be hundreds of times brighter than indoor light. But why does playing outside prevent us from
becoming short-sighted? _____
So be outdoors. It doesn't matter if that time is spent having a picnic or playing sports.
A. Scientists believe that natural light has a special chemical which stops the eyeball from growing out of shape
and prevents people becoming short-sighted.
B. But when people begin to go to school and spend little or no time outdoors, the number of short-sighted
people gets larger.
C. It challenges the belief that short-sightedness is caused by computer use, watching TV or reading in weak
light.
D. Both groups spent a similar amount if time reading, watching television and playing computer games.
E. Children don't know how to use their eyes correctly.
