Subsistence level means: just covering one's own needs, not producing too much and not enough to sell and to get very rich.
So the correct answer is :<span>C. they produce only enough to feed their family, and they have little left over to sell at a market </span>
Answer: Homogamy
Homogamy is a term used in sociology to describe the tendency for sexually partnered couples to resemble each other, in some culturally important way. It can be based on status, class, gender, ethnicity, or religion, or age. It is a form of assortative mating.
Answer: Across subjects multiple-baseline design
Explanation: The single case design involves experiment whereby only one group is used as to make inference in the study, the control group and treatment group aren't distinct. When behavior is measured or observed in two or more participants belonging to a single group by delivering a the same intervention or treatment at different poinf in time. In the scenario above, the smile and eye contact is the treatment being delivered or used on the participants to measure the the level of responsiveness of the participants. After trying the treatment on the first subject, the treatment was so test on the other participants, hence
