PART B: Which detail from the text best supports the answer to Part A?

A
“A new study, published in February in the Journal of Youth and Adolescence, takes a more nuanced look, attempting to determine just how much each hour less per night really costs” ( Paragraph 1)
B
“Although teenagers need about nine hours of sleep a night on average, according to the National Institutes of Health, only 3 percent of students reported getting that amount” ( Paragraph 2)
C
“These correlational findings do not prove that lack of sleep is causing these problems. Certainly the reverse can be true: depression and anxiety can cause insomnia.” ( Paragraph 3)
D
“‘But the majority of the research evidence supports the causal direction being lack of sleep leading to problems rather than the other way around’” ( Paragraph 3)

D "But the majority of the research evidence supports the causal direction being lack of sleep leading to problems rather than the other way around" ( Paragraph 3)

Explanation:

Although there are not enough information here, I'm assuming this question is related to the article "Teenagers Who Don’t Get Enough Sleep at Higher Risk for Mental Health Problems".

The main idea of this article is to show correlation between the lack of sleep and likelihood of mental health problems in teenagers. Although this correlation isn't undeniable, due to many factors that can cause mental problems including social status, genetics, environment etc, it obviously exists.

This idea is best supported by a sentence from paragraph 3 which provides evidence that the research data support the casual direction being lack of sleep leading to mental problems.

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