Read the following passage and answer the question given below : The motivation for deep-space travel is shifting from discovery to economics. The past year has seen a flurry of proposals aimed at bringing celestial riches down to Earth. No doubt this will make a few billionaires even wealthier, but we all stand to gain: the mineral bounty and spin-off technologies could enrich us all. But before the miners start firing up their rockets, we should pause for thought. At first glance, space mining seems to sidestep most environmental concerns: there is (probably!) no life on asteroids, and thus no habitats to trash. But its consequences – both here on Earth and in space – merit careful consideration. Part of this is about principles. Some will argue that space’s “magnificent desolation” is not ours to despoil, just as they argue that our own planet’s poles should remain pristine. Others will suggest that glutting ourselves on space’s riches is not an acceptable alternative to developing more sustainable ways of earthly life. History suggests that those will be hard lines to hold, and it may be difficult to persuade the public that such barren environments are worth preserving. After all, they exist in vast abundance, and even fewer people will experience them than have walked through Antarctica’s icy landscapes. There’s also the emerging off-world economy to consider. The resources that are valuable in orbit and beyond may be very different to those we prize on Earth (see “Space miners hope to build first off-Earth economy“). Questions of their stewardship have barely been broached – and the relevant legal and regulatory framework is fragmentary, to put it mildly. Space miners, like their earthly counterparts, are often reluctant to engage with such questions. One speaker at last week’s space-mining forum in Sydney, Australia, concluded with a plea that regulation should be avoided. But miners have much to gain from a broad agreement on the for-profit exploitation of space. Without consensus, claims will be disputed, investments risky, and the gains made insecure. It is in all of our long-term interests to seek one out. Which choice provides the best evidence for the answer to the previous question ?