Final answer:
Option b is supported by the context provided, as it reflects that restaurants employ different strategies to reduce environmental impact, and environmental costs are often minimal compared to other operational costs for businesses.
Step-by-step explanation:
The Bloomberg Intelligence Restaurant Primer likely points out various strategies and challenges faced by restaurants in an effort to manage their environmental impact. Option b, which states that a challenge of comparing restaurants' environmental impact is that restaurants are employing different strategies from each other to minimize resource intensity, seems the most plausible given the context provided.
The information implies that, while some low-income countries may reduce environmental standards to attract businesses, the reality is that for many businesses, these environmental costs are minimal compared to other costs such as labor, infrastructure, and proximity to customers and suppliers. Therefore, the decision on where to locate business operations is likely to be governed by a variety of factors, among which environmental regulations are just one and often not the most critical.
The race-to-the-bottom scenario, where countries lower standards to attract businesses and businesses relocate accordingly, does not align with practical business considerations that prioritize operational efficiency and access to markets over marginal savings in environmental compliance costs.