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The US Mint makes money. It doesn't make all kinds, just coins. At first, the US Mint made one cent and one-half cent pieces. Through the years, it has made many coins, including a $20 gold piece. Today, the mint makes all of the coins we use to shop. It makes coins for special occasions too. The mint also stamps the designs for special medals.
The main idea in this passage is:
A. The US Mint makes all kinds of money.
B. The US Mint make $20 gold pieces.
C. The US Mint makes all the coins we use to shop.
D. The US Mint makes coins for special occasions.
What is C. The US Mint makes all the coins we use to shop.?