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The Truth about Left-Handed People
About 90% of people in the world today arc right-handed. The other 10% arc left-handed, including Obama, the President of the US. Every day, left-handed folks quietly face problems. It could be something as simple as driving a car or using a can opener.
Why are so few of us left-handed? One theory is that handedness (hand preference) could be a result of genetics. Scientists say that there are two genes（基因）associated with handedness. One is the D gene. It is more frequent in the population and promotes（促成）right-hand preference. The other is the C gene. It has the ability to promote a preference for cither hand．When the C gene is present, there is a 50% chance that a person could be right- or left-handed.

Another theory has to do with human brains, which arc made up of two halves. If the left half is more powerful, then one is most likely right-handed. But with left-handers, it is more complicated．Seventy percent of them are also left-brain dominant（占优势的）.
During the 18th and 19th centuries, left-handedness was considered a disability. But not all of the myths about left-handers are bad. One myth suggests that they are more creative and smarter than the right-handers. So far scientific research has yet to f
A.True
B.False
C.Not Given

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