Question 9 is based on the passage you have just heard.

原文：

    (9)Mothers have been warned for years that sleeping with their newborn infant is a bad idea because it increases the risk that the baby might die unexpectedly during the night. (10)But now Israeli researchers are reporting that even sleeping in the same room can have negative consequences, not for the child, but for the mother. Mothers who slept in the same room as their infants, whether in the same bed or just the same room, had poorer sleep than mothers whose babies slept elsewhere in the house: They woke up more frequently, were awake approximately 20 minutes longer per night, and had shorter periods of uninterrupted sleep. These results held true even taking into account that many of the women in the study were breast-feeding their babies. Infants, on the other hand, didn't appear to have worse sleep whether they slept in the same or different room from their mothers. The researchers acknowledge that since the families they studied were all middle-class Israelis, it's possible the results would be different in different cultures. Lead author Liat Tikotzky wrote in an email that the research team also didn't measure fathers' sleep, so it’s possible that their sleep patterns could also be causing the sleep disruptions for moms. Right now, (11)to reduce the risk of sudden infant death syndrome, the American Academy of Pediatrics recommends that mothers not sleep in the same bed as their babies, but sleep in the same room. The Israeli study suggests that doing so may be best for baby, but may take a toll on Mom.

9. What is the long-held view about mothers sleeping with newborn babies?

解析：B。四个选项都与it的影响有关，从mother, infant可以推测题目询问某事对妈妈或婴儿的影响。录音一开始就指出：妈妈和新生儿睡在一起不好，因为这会增加婴儿夜间意外死亡的风险。B选项“会增加婴儿死亡的风险”与录音信息一致，故正确。A选项“可能会使妈妈精神苦闷”并未提及；C选项“可能影响妈妈的健康”是最新发现，不是长期的观点；录音中说婴儿的睡眠并不会受到影响，而且这是最新研究，不是长期观点，故排除D选项“会妨碍婴儿睡眠”。