Final answer:
Increasing the width and capacity of roadways leads to urban sprawl and increased greenhouse gas emissions, which opposes the principles of sustainable development.
Step-by-step explanation:
Increasing the width and capacity of roadways tends to encourage urban sprawl, answering the original question with option (a). Urban sprawl refers to the spread of urban development into areas outside of cities, and larger highways make it easier for people to live farther from where they work. As sprawl increases, so does the reliance on automobiles, which can lead to higher greenhouse gas emissions. This growth pattern contradicts sustainable development, which aims to meet present needs without compromising the ability of future generations to meet their own needs, and often involves limiting sprawl and promoting other forms of transportation like public transit.
Environmental activists often highlight problems with current commuting infrastructure, pointing out that a heavy emphasis on road development for cars contributes to environmental degradation, increased emissions, and loss of natural landscapes. Rather than encouraging sprawling suburbs, activists and planners may advocate for 'smarter' development, which includes in-filling existing areas and establishing transportation options that reduce reliance on personal vehicles.
Ultimately, the goal for sustainable city planning should be to balance the need for transport connectivity with the preservation of the environment and the minimization of greenhouse gas emissions, adopting concepts like countryside biogeography or reconciliation ecology.