Caffeine is a central nervous system (CNS) stimulant of the methylxanthine class. It is the world's most widely consumed psychoactive drug. Unlike many other psychoactive substances, it is legal and unregulated in nearly all parts of the world. It is
found in the seeds, nuts, or leaves of a number of plants native to South America and East Asia and confers on them several
survival and reproductive benefits. The most well known source of caffeine is the coffee bean. Beverages containing caffeine are
ingested to relieve or prevent drowsiness and to improve performance. To make these drinks, caffeine is extracted by steeping
the plant product in water, a process called infusion. Caffeine-containing drinks, such as coffee, tea, and cola, are very popular; in
2005, 90% of North American adults consumed caffeine daily.
The passage suggests that one effect of ingesting caffeine is
es )
A)
the prevention of drowsiness.
B)
a decrease in hunger.
C)
an increase in depression.
D)
extreme anger.