一政府机构出版了航空公司的信用等级，把晚点航班比例最小的航空公司列入最高信誉等级，这家机构的目的是要建立一个客观的方法来衡量不同航空公司在遵守出版的航空时刻表方面的相对有效性。以下哪项如果为真，将使得这家机构信用等级的使用无效( )

A．班机经常由于糟糕的天气条件而晚点，而某些航空公司受坏天气影响要多于其他航空公司

B．所有航空公司的班机时刻表允许班机有额外的时间进入或离开繁忙的机场

C．航空公司的职员意识到这家政府机构正在监管所有晚点的航空公司班机

D．当且仅当班机比预定到达时间晚到15分钟以上时，才定义为班机晚点，并且记录他们晚点超过15分钟的时间

Research studies show that there are some fundamental (1) between men and women in their attitudes to (2) matters. Women are far more likely to save for their children’s (3) and to save up to buy a (4) . Men tend to save for a (5) , and for their (6) . But in fact the need for women to save for their old age is far (7) than for men. Throughout the world, women are likely to live many years (8) than men. Furthermore it is the (9) women who will most often have to look after the children and thus they need more (10) to look after not just themselves but others. Women today need to look ahead, think ahead, not wait until they’re under (11) .
A number of (12) have been set up to help them do this. Some educational institutions offer night (13) in Money (14) . They can be given (15) on different ways of saving. It is usually advised that at least (16) of a person’s savings should be in low-risk investments but for the rest, (17) advisors often advise taking some (18) risks. Initiatives such as this can give women the economic (19) and knowledge they need for a comfortable, (20) retirement.