One of the most significant ways to start building sustainability is to stop spending money on highways and instead prioritize sustainable transport, as seen in much of Portland's sustainability plans of the 1980s (Newman & Jennings 2008, Ch, 2). Why was the main rationale? Group of answer choices Highways undermines urban economies and they create expensive car dependence Car-dependent cities use over 20 of their income on transport Cars decrease space efficiency (on the roads and parking) All of the above