Which of the following best paraphrases the underlined sentence in paragraph 4?

It is the digital devices used for certain complicated academic tasks at university that are distracting students from more important assignments.

Some academic work at university requires students' genuine concentration, which has become a complicated matter with bad-quality digital tools.

Not only certain academic assignments at university but also the digital tools useful for these tasks are causing complicated problems for students.

What complicates matters is that digital devices necessary for completing some university work can interfere with students' concentration.