Which supporting detail is written objectively? i imagine many prospectors were homesick living so far from civilization in the yukon wilderness. jack london is brilliant in providing interesting details such as the chewing-tobacco “beard.” thousands of men came to canada seeking their fortune in the 1890’s, which explains why few were successful. the great north american traits of resourcefulness and determination are beautifully illustrated.

The correct answer is - Thousands of men came to Canada seeking their fortune in the 1890’s, which explains why few were successful.
This is the only objective supporting detail because it is a fact - it is something that actually happened and is recorded in history books. On the other hand, all of the remaining options above are the author's personal and subjective opinions (seen by the usage of words such as homesick, interesting, beautifully, etc.) and thus cannot be objective.