17. The writer wants to add more information to the second paragraph (sentences 5–9) to support the main argument of the paragraph. All of the following pieces of evidence help achieve this purpose EXCEPT which one?

- At least one study points to light exposure in the evening as a contributing factor in teens’ changing sleep patterns.

- Researchers at Boston Children’s Hospital claim that the total amount of sleep teens receive is less important to self-regulation than when that sleep occurs.

- As children enter adolescence, their circadian rhythm shifts; they remain alert later in the evening and have trouble sleeping before 11:00 p.m.

- In teens, a chemical that makes people feel tired is released from roughly 11:00 p.m. to 8:00 a.m.

- Pediatricians recommend that children up to age 12 get 9 to 12 hours of sleep per night; the recommendation for teens is only slightly lower.