Final answer:
On average, over half of a college or university campus's greenhouse gas emissions is from commuting, with vehicles being substantial contributors to carbon footprint. Infrastructure improvements and energy consumption reduction are also critical in managing overall emissions from buildings. The correct answer is option: b. commuting.
Step-by-step explanation:
On average, over half of a college or university campus's greenhouse gas emissions is from commuting. Transportation systems, including the daily movement of students' vehicles across campus, significantly contribute to these emissions.
With vehicles creating about 20% of greenhouse gas emissions in the United States, efforts to mitigate climate change must include reducing vehicle usage and encouraging alternative modes of transport. Simple actions like walking instead of driving can notably reduce one's overall carbon footprint.
In the broader context, considering infrastructure and incentivizing the reduction in energy consumption are also pivotal strategies in managing greenhouse emissions from buildings which form a significant part of the emissions alongside commuting.