I believe it’s the Last option. I searched it up for a background check and this is what I found :)
The diction of Steinbeck here in apparently describing the dustbowl conditions of the Dirty Thirties is speaking of "tenant men" or presumably men who were tenant farmers perhaps who were allowed to live on the land in return for working it and that they "scuffed" their way home indicates that the dust was so thick they had to scuff but also perhaps that since they could barely make a living under the poor agricultural conditions they did not walk confidently but scuffed.
Joe Shmoe's determination that "What is Pluto" is a credible source is based on the fact that the source is an article from a reputable website. The website is credible because it is backed by a reputable organization, such as the National Science Foundation. The article is also credible because it is written by an expert in the field of astronomy.
