题目内容：

Popeye the Sailor first became a popular cartoon in the 1930s.The sailor in that cartoon ate lots of spinach(菠菜) to make him strong. People watched him, and they began to buy and eat a lot more spinach. Popeye helped sell 33 percent more spinach than before! Spinach became a necessary part of many people’s diets. Even some children who hated the taste began to eat the vegetable.

Many people thought that the iron in spinach made Popeye strong, but this is not true. Spinach does not have any more iron than any other green vegetable.

People only thought spinach had a lot of iron because the people who studied the food made a mistake. In the 1890s, a group of people studied what was inside vegetables. This group said that spinach had ten times more iron than it did. The group wrote the number wrong, and everyone accepted it.

Today, we know that the little iron there is in spinach cannot make a difference in how strong a person is. However, spinach does have something else which the body needs—folic acid(叶酸).

It is interesting to point out that folic acid can help make a person strong. Maybe it was really the folic acid that made Popeye strong all along.   

1.A good title for this reading passage is______.

A．Popeye the Sailor

B．The Truth About Spinach

C．A Mistake with Numbers

D．Folic Acid Makes You Strong

2.Why did many people eat spinach after they saw Popeye the Sailor?

A．They thought spinach made them strong.

B．They thought Popeye was funny.

C．Spinach had a lot of iron.

D．People liked folic acid.

3.A research group told people that spinach______.

A．made Popeye strong

B．was a green vegetable

C．had less iron than other green vegetables

D．had more iron than other green vegetables

4.Folic acid is ______.

A．something in food

B．a vegetable

C．dangerous

D．a certain kind of spinach