Which of the Following Is Not True About Concentration

Which of the following is not true about concentration?

A) You can concentrate better when you are interested in the material.
B) you can maintain your concentration during long study sessions by switching subjects every hour.
C) Many students use escapist techniques when they have difficulty concentrating on a task.
D) Many students are able to maintain their concentration at a high level even though they read and respond to text messages when they are studying.