Why does the author mention labor and wages in Paragraph 5？
A. To suggest that commercial entities are different from most secondary groups.
B. To explain the reason why most secondary groups exist.
C. To contrast these resources with tangible items found in secondary groups.
D. To characterize the nature of exchanges within secondary groups.
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In Paragraph 3, the author states that primary groups are largely responsible for
A. shaping how their members relate to their social environment.
B. making sure societies work together towards a common goal.
C. forming organizations that undertake community development.
D. introducing new sets of beliefs and values to human society.
According to Paragraph 4, Caulerpa taxifolia is known as "killer algae" because
A. it has colonized a variety of underwater environments.
B. it eliminates native plants and drives away native animals.
C. it is toxic to people who come into contact with it.
D. it grows too deep for other species to reach it.
According to Paragraph 6, one similarity between primary and secondary groups is that they
A. give rise to technological development.
B. are absent in less-developed nations.
C. can be observed in all kinds of societies.
D. are essential to the health of societies.
What determines the price of a goods in a market economy？
A. The cost of all elements of its production.
B. The cost of not making other goods.
C. The efficiency of the manufacturing process.
D. The quantity of material supplied.
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