The passage may have been selected from a book on ______.

A．the former records data more excruciatingly than the latter does
B．the data collected by the latter are biased by perceptions and judgements
C．the former collects data from self-reports or interview surveys
D．the former reconstructs consumer behaviors directly from material reality

A．is humorous because it is ridiculous to search the refuse
B．is based on a serious rationale and it is just what the archaeologists have done
C．is just a guess for it is impossible for archaeologists to do such a thing
D．is interesting because archaeologists can't learn anything while doing so