Final answer:
John Krakauer worked for the magazine Outside, not National Geographic, which is known for its global coverage and large readership.
Step-by-step explanation:
John Krakauer, the journalist and author known for his adventure and mountaineering writing, worked for the magazine Outside. Although National Geographic is a prominent magazine with a wide readership and acclaimed coverage, Krakauer's work was not primarily associated with it. Instead, his writings have been featured in Outside, a publication that focuses on outdoor recreation, adventure, and environmental issues.