A、A good academic thesis. B、A quick search on the Internet. C、Applying theory to practice. D、Idea exchanges with their teachers.

Teachers say the digital age has had a good influence and a not-so-good influence on this generation of American teenagers. More than 2,000 middle and high school teachers took an online survey. Researchers also spoke with teachers in focus groups.
    Three-quarters of the teachers said the Internet and digital search tools have had a "mostly positive" effect on their students’ research habits and skills.(16)But 87 percent agreed that these technologies are creating an " easily distracted generation with short attention spans". And 64 percent said the technologies "do more to distract students than to help them academically".(17)Many students think "doing research" now means just doing a quick search on Google.
    Judy Buchanan is deputy director of the National Writing Project and a co-author of the report.(18)Ms. Buchanan says digital research tools are helping students learn more, and learn faster.
    "Teachers really embrace these tools because they are ways to make some of learning exciting and engaging. Young people embrace these tools. And the goal is to really help them become creators of content, and meaningful content, and not just sort of consumers. "
     (19)But one problem the survey found is that many students are lacking in digital literacy. In other words, they trust too much of the information they find on the Internet. Judy Buchanan says these students have not developed the skills they need to judge the quality of online information. Many teachers are also concerned that the Internet makes it easy for students to copy work done by others instead of using their own abilities.
16. What impact does digital age have on students according to teachers?
17. What does "doing research" mean to many students?
18. What does Ms. Buchanan say about digital research tools?
19. What is the problem found in the survey?