Hunter lived at high altitude and hike frequently while Nick lived at seal level, so 
OPTIONS:
- Hunter got altitude sickness when they drove high up the mountain.
- Nick got altitude sickness when they drove high up the mountain.
Nick got altitude sickness when they drove high up the mountain.

Adam was never able to discover the location of Kyle, even after years of 
OPTIONS:
- Adam being looked for.
- Kyle being looked for.
Kyle being looked for.

She became extremely educated by reading books and watching videos. The 
OPTIONS:
- books were often musty.
- videos were often musty.
books were often musty.