In a world where hunger kills more people each year than malaria, tuberculosis and AIDS combined, Elon Musk's bold proposition in October 2021 sparked an unusual yet critical conversation.

The tech billionaire, known for electrifying industries and aiming for Mars, turned his attention back to Earth when David Beasley, head of the UN's World Food Programme (WFP), pleaded for billionaires to step up now "on a one-time basis."

Beasley declared on CNN that "$6 billion to help 42 million people that are literally going to die if we don't reach them. It's not complicated."

Musk, never one to shy away from a public challenge, fired back on X (formerly Twitter): "If WFP can describe on this Twitter thread exactly how $6B will solve world hunger, I will sell Tesla stock right now and do it."