D. Although I suppose it depends on how 'early' these humans were.
Early humans survived harsh environments by utilizing natural shelters or creating their own using available materials. They developed basic technologies, like stone tools, for hunting, food preparation and clothing creation. They also formed communities and migrated together for survival, eventually developing farming practices that led to more stable settlements. ;
Early humans survived harsh environments primarily by living in caves and building temporary shelters from available materials. They formed tight-knit communities that shared resources, which was crucial for their survival. Their adaptability to changing climates, particularly during the Ice Age, was vital to their success as a species.
;