题目内容：

阅读下面短文，从每小题所给的A、B、C三个选项中，选出一个最佳选项。

The next time you are out walking your dog, be sure to keep your eyes on the ground. Maybe you can find some treasures. That is exactly what happened to a California couple who recently happened to find the most valuable ancient gold in North America.

John and Mary, a couple, lived in Northern California's Gold Country.One day they were walking their dog along the road as usual. However, this time around, John noticed a rusty bottle sticking out(凸出) from the ground. They decided to take a closer look, and then they unearthed it with a stick and took it home.

The can was very heavy, making the couple guess that it was filled with paint. However, when John opened it and saw the side of a shiny coin, he knew he had found gold!

The couple immediately returned to the area with a small shovel to see if there were any more bottles to be found. Sure enough, they found one more. This one had broken and scattered(散开) all its treasures into the ground below. And that was not all—over the next few days the couple found six more in the area. According to the dates of the coins, as well as, the conditions of the metal cans, experts believe that the gold was buried sometime in the late 19th century, right after the California's Gold Rush. John thought that the can that was sticking out, was a mark for whoever buried the treasure there. For reasons that nobody will ever know, he/she never returned to get it back.

1.What does the first paragraph mainly tell us?

A. We should look at the ground while walking.

B. The couple found ancient gold while walking.

C. John and Mary usually walked the dog together.

2.The underlined word “unearthed” means “________ ” in Chinese.

A. 挖    B. 埋葬    C. 鉴定

3.What was in the can?

A. Paint.    B. Drink.    C. Gold.

4.How many cans did the couple find all together?

A. One.    B. Two.    C. Eight.

5.The writer agreed that no one knew  ________.

A. why nobody got the cans back

B. what was in the cans

C. how the can was found