Madrid was hailed as a public health beacon last November when it rolled out ambitious restrictions on the most polluting cars. Seven months and one election day later, a new conservative city council suspended enforcement of the clean air zone, a first step toward its possible demise.

    Mayor José Luis Martínez-Almeida made opposition to the zone a centrepiece of his election campaign, despite its success in improving air quality. A judge has now overruled the city’s decision to stop levying fines, ordering them reinstated. But with legal battles ahead, the zone’s future looks uncertain at best.

    Among other weaknesses, the measures cities must employ when left to tackle dirty air on their own are politically contentious, and therefore vulnerable. That’s because they inevitably put the costs of cleaning the air on to individual drivers—who must pay fees or buy better vehicles—rather than on to the car manufacturers whose cheating is the real cause of our toxic pollution.

    It’s not hard to imagine a similar reversal happening in London. The new ultra-low emission zone (Ulez) is likely to be a big issue in next year’s mayoral election. And if Sadiq Khan wins and extends it to the North and South Circular roads in 2021 as he intends, it is sure to spark intense opposition from the far larger number of motorists who will then be affected.

    It’s not that measures such as London’s Ulez are useless. Far from it. Local officials are using the levers that are available to them to safeguard residents’ health in the face of a serious threat. The zones do deliver some improvements to air quality, and the science tells us that means real health benefits—fewer heart attacks, strokes and premature births, less cancer, dementia and asthma. Fewer untimely deaths.

    But mayors and councilors can only do so much about a problem that is far bigger than any one city or town. They are acting because national governments—Britain’s and others across Europe—have failed to do so.

    Restrictions that keep highly polluting cars out of certain areas—city centres, “school streets”, even individual roads—are a response to the absence of a larger effort to properly enforce existing regulations and require auto companies to bring their vehicles into compliance. Wales has introduced special low speed limits to minimise pollution. We’re doing everything but insist that manufacturers clean up their cars.

答案精析：本题为细节题。根据题干中的weakness和the city-level measures可定位至原文第三段。该段讲到，城市所采取的必要措施在处理空气污染问题上存在政治争议，因此很脆弱。这是因为这些措施不可避免地把净化空气的成本推给了司机个人。由此可推知，城市为治理空气污染所采取的措施给司机个人增加了负担，D项中的individual motorists为原文中individual drivers的同义替换词，故正确答案为D。

错项排除：A项利用car manufacturers进行干扰，原文第三段第二句说到，城市不可避免地把净化空气的成本推给了司机个人，而不是汽车制造商。由此可见，城市所采取的的措施对汽车制造商并没有偏见，反而是对其有利的，故A项错误。B项中的“不切实际”在原文中并无依据，故排除。C项利用原文中的politically和vulnerable这类细节信息进行干扰，但原文说的是城市所采取的措施在处理空气污染问题上存在政治争议，因此很脆弱，并没有说该举措对政治家过于温和，故C项错误。

长难句分析：That’s because they inevitably put the costs of cleaning the air on to individual drivers—who must pay fees or buy better vehicles—rather than on to the car manufacturers whose cheating is the real cause of our toxic pollution.

本句主干为That’s because…，是主系表结构。because引导表语从句，从句的主干为they put the cost on to individual drivers…rather than on to the car manufacturers…。破折号中间的内容为who引导的定语从句，修饰前面的individual drivers。rather than引导比较状语，表示“而不是……”，修饰前面的because they…on to individual drivers。whose同样引导定语从句，修饰car manufacturers。

句意为：这是因为这些市级措施不可避免地把净化空气的成本推给了司机个人——他们必须支付费用或购买更好的汽车——而不是汽车制造商，这些制造商的欺骗行为才是造成有毒空气污染的真正原因。