Today, in our environmental science lecture, we'll discuss the impact of urban farming. One key study found that rooftop gardens can reduce a building's energy consumption by up to 30 percent, mainly by providing insulation. However, the initial cost of setting up such a garden is quite high, often exceeding 50,000 dollars for a medium-sized roof. Despite this, the long-term savings on energy bills and the reduction in stormwater runoff make it a viable option for many cities. Another benefit is the local food production, which cuts transportation emissions.
❓ According to the lecture, what is the main reason rooftop gardens reduce energy consumption?
A. A. They produce food locally, cutting transportation emissions.