READING SKILL
Text 1
Scientists say that smartphones are changing the shape of people's skulls. Some people are spending so long looking at smartphones that a small bony bump is appearing above their neck. Doctors say the bump is large enough to feel by pressing the bottom of the skull, just above the neck. Dr David Shahar, a health scientist at the University of The Sunshine Coast in Australia, spoke to the BBC about the discovery. He said: "I have been a clinician for 20 years, and only in the last decade, increasingly, I have been discovering that my patients have this growth on the skull." The bump is becoming more frequent among 18 to 30-year-olds who spend many hours a day hunched over their smartphone.
1) According to the text 1, choose the correct answer. What is the main cause of the appearance of a bony bump on the neck?
Select one of the following: