Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.

WORTH COLLECTING

Would you be worried if your classmate told you that he was a philatelist? Would you call a doctor or call the police? Actually, there is no reason to be concerned. A philatelist is just a person who collects stamps!

Stamp collecting has been around for well over 150 years. People began collecting stamps soon after adhesive postage stamps (stamps with glue on the back) were introduced in London in 1840. Today, according to Boy’s Life magazine, stamp collecting is the most practiced hobby in the world.

Some people collect stamps just for fun. These people may just want to collect stamps with animals or famous people on them. Or maybe they want to collect all the stamps issued by one particular country. Other people collect stamps that they think will be valuable down the road. Such collectors ask three questions to determine if a stamp is worth collecting and what its value might be.

First, how many of a particular stamp were made? Next, how popular is the stamp? Finally, what is the condition of the stamp? If a stamp has a low print run, a popular picture or design, and is in excellent condition, this stamp may be worth a lot of money. In 1980, a one-cent British Guinea stamp issued in 1856 went for $935,000!

(Source: Reading Challenge 1)

Wind is a clean source of renewable energy (2)_______ produces no air or water pollution