I met with this question while doing SAT reading,
But change the conversation to food, and suddenly efficiency doesn’t look so good. Conventional industrial agriculture has become incredibly efficient on a simple land to food basis.Thanks to fertilizers,mechanizationandirrigation, each American farmer feeds over 155 people worldwide.
The answer gives 'straightforward' as the best definition,but I still can't wrap my head around it. Actually I feel confused about the whole second sentence. What does it mean?