Women who live in areas with higher levels of outdoor light at night may be at higher risk

Women who live in areas with higher levels of outdoor light at night may be at

higher risk for breast cancer， according to a study from Harvard T.H. Chan

School Of Public Health. The link was stronger among women who worked night

shifts.

Previous studies have suggested that exposure to light at night may lead to

decreased levels of the homone melatonin ， which can disrupt circadian

rhythms—our internal ’clocks’ that govern sleepiness and alertness—and， in turn，

lead to increased breast cancer risk.

The new study， the most comprehensive to date to examine possible links between

outdoor light at night and breast cancer， looked at data from nearly 110，000

women enrolled in the Nurses’ Health Study II from 1989-2013. The researchers

linked data from satellite images of Earth taken at night time to residential

addresses for each study participant， and also considered the influence of night

shift work. The study also factored in detailed information on a variety of

health and socioeconomic factors among participants.

Women exposed to the highest levels of outdoor light at night—those in the top

fift— had an estimated 14% increased risk of breast cancer during the study

period， as compared with women in the bottom fifth of exposure， the researchers

found. As levels of outdoor light at night increased， so did breast cancer

rates.

However， the association between outdoor light at night and breast cancer was

found only among women who were premenopausal and those who were current or past

smokers. In addition， the link was stronger among women who worked night shifts，

suggesting that exposure to light at night and night shift work contribute

jointly to breast cancer risk.

What can we learn from the first paragraph？

A.Women who live with higher levels of outdoor light may be at higher risk for cancer.

B.Men who live with higher levels of outdoor light may be at higher risk for cancer.

C.Women who worked night shifts may be at higher risk for breast cancer.

D.Men who worked night shifts may be at higher risk for breast cancer.

The underlined word in the Second Paragraph means_______.A.Awakening

B.awareness

C.wake

D.waking

According to previous studies， which of the following factors leads to increased breast cancer risk directly？A.Night shift work

B.Higher levels of outdoor light

C.Higher levels of the hormone melatonin

D.Health and socioeconomic factors

Which of the following can be the best title of the passage？A.Higher levels of outdoor light at night may be increasing the risk for breast cancer

B.The study of women’s work context

C.Higher levels of the hormone melatonin may be increasing the risk for breast cancer

D.The study of breast cancer

Which one is TURE？A.The association between outdoor light at night and breast cancer was found among all women.

B.According to the new study， as levels of outdoor light at night increased， so did breast cancer rates.

C.Women who were premenopausal were at lower risk for breast cancer.

D.Only night shift work contributes to breast cancer risk.

请帮忙给出每个问题的正确答案和分析，谢谢！