单项选择题

The scandal at Harvard University in which authorities are investigating whether nearly haft of a class of 279 students cheated on a take-home final exam raises a number of questions, including this: Does everybody cheat
Dozens of Harvard University students may have wrongly shared answers on a final exam, an "unprecedented" case of suspected academic dishonesty. Sanctions for students found guilty of cheating include leaving Harvard for a year.
Harvard, like most U.S. colleges and universities, has never had an honor code, although the Associated Press reports that it is giving "renewed consideration" to the idea as a result of the scandal.
So, does everybody cheat
Not quite, but studies show that most students cheat at one time or another.
A survey of 40,000 high school students found that more than half of teenagers said they had cheated on a test in the previous year, and 34 percent said they had done it more than twice. One-third of the students said that they had plagiarized an assignment with the help of the Internet.
The consequences for the country may be significant. A 2009 study about the relationship between high school attitudes and behavior and later adult conduct found that people who cheated on exams in high school two or more times are more likely to be dishonest later in life than those who never cheated in high school.
Meanwhile, we’ve seen successive scandals involving cheating by the adults in school—teachers and principals—as a result of the growing importance of standardized tests. As the stakes associated with the scores have risen—the tests are used to gauge not only student achievement, but also teacher effectiveness, school and district quality—more people have taken desperate measures to ensure better scores. Not an excuse, just an explanation.
Modern technology makes cheating much easier. Cheating cases have been documented in 30 states over the past three academic years. Some students, including those at virtual schools, sometimes put entire quizzes on the Internet, and the same exams are used repeatedly by teachers.
Back at Harvard, a culture of cheating persists. "There’s a lot of pressure internally and externally to succeed at Harvard, and when kids who are not used to failing feel these things, it can really bend their ethics in ways I didn’t expect to see," author Eric Kester told ABC News. Which of the following is true about teachers and principals according to this passage

A. They can benefit from high scores of students.
B. They seldom punish the offenders on a test.
C. They are reluctant to become more effective.
D. They have never used standardized tests.