To answer this question, think about which one would provide you with the least information about how an immigrant's day-to-day life. If you're still struggling, think about what each option
does tell you.
A. Tells about urban employment where many immigrants were working. It's fiction (presumably), but I think it's safe to assume that it's got some basis in fact AND the fictionalized part is the author's interpretation of feelings and mood.
B. This seems like an excellent source. It's primary (so no interpretation) and it's on point. It is only one perspective, but it's an excellent one.
C. Well, this gives you an idea of the hours worked, the job worked, the name of the person and the pay. It is reasonable to assume that the factory worker is an immigrant based on the context of the question and the common occupations of immigrants. This is a decent resource.
D. Presumably, ads are written to convince an audience to buy. This resource can give you an idea of what people were being sold, and, to some extent, what they were buying. The promises in the ad can indicate what sort of things people were looking for and what they were responsive to. This is decent, despite being from the early twentieth-century. It tells you how the immigrants lives may have progressed.
E. This is an ad for blueprints, not the blueprints themselves. While it may be interesting, blueprints are marketed to builders (not usually individuals), so it's a niche market. Further, it doesn't tell you about the structure of the homes or how they looked or how they were built. It only tells you (presumably) that a company has blueprints for homes that they want to sell.
E is your answer.