1. What is the most widely used clothing material? 
　　　 A) Wool.
　　　 B) Cotton.
　　　 C) Animal skin.
　　　 D) Feather.

　　2. How many people in the world wear clothing of cotton? 
　　　 A) About 4/10 of the population.
　　　 B) About 3/4 of the population.
　　　 C) About 30% of the population.
　　　 D) About 43 % of the population.

　　3. Cotton was made into cloth _____. 
　　　 A) about 1,500 years ago
　　　 B) in the fifteenth century
　　　 C) about 3,500 years ago
　　　 D) in the eighth century