High school dropouts earn an average of $9

问题：

High school dropouts earn an average of $9,000 less per year than graduates. Now a new study dispels a common belief why they quit. It’s much more basic than flunking out.
Society tends to think of high school dropouts as kids who just can’t cut it. They are lazy, and perhaps not too bright. So researchers were surprised when they asked more than 450 kids who quit school about why they left.
"The vast majority actually had passing grades and they were confident that they could have graduated from high school. " John Bridgeland, the executive researcher said. About 1million teens leave school each year. Only about half of African American and Hispanic student will receive a diploma, and actually all dropouts come to regret their decision. So, if failing grades don’t explain why these kids quit, what does Again, John Bridgeland: "The most dependable finding was that they were bored. " "They found classes uninteresting; they weren’t inspired or motivated. They didn’t see any direct connection between what they were learning in the classroom to their own lives, or to their career aspirations. "
The study found that most teens who do drop out wait until they turn sixteen, which happens to be the age at which most states allow students to quit. In the US, only one state, New Mexico, has a law requiring teenagers to stay in high school until they graduate. Only four states: California, Tennessee, Texas and Utah, plus the District of Columbia, require school attendance until age 18, no exceptions, another researcher, says raising the compulsory attendance age may be one way to keep more kids in school.
"As these dropouts look hack, they realize they’ve made a mistake. And anything that sort of gives these people an extra push to stick it out and it through to the end, is probably helpful measure. "
New Hampshire may be the next state to raise its school attendance age to 18. But critics say that forcing the students unwilling to continue their studies to stay in school misses the point—the need for reform. It’s been called for to reinvent high school education to make it more challenging and relevant, and to ensure that kids who do stick it out receive a diploma that actually means something.

In the last paragraph, the writer is trying to ______.

A．analyze the reason why students quit school
B．suggest raising the compulsory attendance age
C．raise awareness of reforming high school education
D．wish to make laws to guarantee no education