Global food production has, in aggregate, kept pace with population growth for decades, yet roughly one in nine people worldwide remains undernourished, and the world wastes close to a third of all food produced between farm and plate. Meeting future demand sustainably will require not just producing more, but producing smarter: cutting post-harvest losses, improving distribution to where need is greatest, and adapting crops to a changing climate, since simply expanding cultivated area further would come at a steep environmental cost.

According to the passage, what is the biggest challenge to world agriculture?