The answer is C, although the other options are important as well, in this case, C is the answer you are looking for
Occupations in the SOC with similar job duties, that require similar skills, education and/ or training are grouped together
I don’t understand the question
B are found in isolated places in the world. This is because we have mostly evolved to a first world society where we work for our shelter and food instead of hunting for things that are necessary.