You should start a new post instead of adding on to an existing post.
That said, I would go with A
Which of the following statements is true??
A) The value of a good may change over time.
B)A highly valued good is always more expensive than a lesser valued good.
C)Highly valued goods are always scarce goods.
D)Rare goods are always scarce goods
E)The scarity of a good is always constant.
I would go with A.
You can eliminate most of the other answers by considering the oxygen as a good. Is it highly valued? Is it particularly scarce, in a relative sense?
The circular flow of economic activity can be summed up as:
A. households earn money by selling their factors of production to firms in the factor market and use that money to buy goods and services from firms in the product market.
B. firms earn money by selling their factors of production to households in the factor market and use that money to buy goods and services from households in the product market.
C. households buy factors of production from firms and use them to produce goods and services, which they sell to other households.
D. households earn money by selling their factors of production to firms in the product market and use that money to buy goods and services from firms in the factor market.
E. firms buy goods and services from other firms, who in turn buy goods and services from yet other firms.