单选题 The cohesiveness (内聚力) of a family seems to rely on members sharing certain routine practices and events. For a growing share of the American labor force , however , working shifts beyond the normal daylight hours- -what we here call "shift work" -makes the lives of families difficult. Existing research shows that both male and female shift workers express high levels of stress and a sense of conflict between the demands of work and family life.' But shift work couples still maintain a traditional attitude to the meaning of marriage and the individual roles of husband and wife. They expressed a willingness to do " whatever it takes" to approximate their view of a proper marriage ,including sacrificing sleep and doing conventional things at unconventional hours. For the majority of couples interviewed , even when wives worked outside their homes, a proper marriage is characterized by a very clear division of roles : husbands are " providers" whose major responsibility is to support the family ;wives are " homemakers" who clean , cook , and care for husbands and children. The women's definitions of a good husband" are typified by the following wife's response: I expect him to be a good provider , and be there when I need him ,loyal about the same things as he would expect out of me , expect that I expect him to dominate over me. But in a manner of speaking, when it's time to be a man I expect him to stand up instead of sitting back expecting me to do everything. To husbands ,a good wife is someone who is: Understanding of what I feel go through at work. I need that respect at work,I hope I get it at work. I want my wife to realize what I expect at work. I don't want her to give me a lot of shit when I come home from work because I don't know if this makes much sense. These views seemed critical to maintain the families of the shift workers小题:What is implied by the author