本题目来源于试卷: IB Economics Unit 2.1: Microeconomics - Demand & Supply, Equilibrium，类别为 IB经济学
[单选题]
Which of the following describes what is happening in the diagram?
I. An increase in quantity demanded
II. An increase in demand
III. The substitution effect
A. I and II only
B. I, II, and III
C. I and III only
D. II and III only
参考答案: C
本题详细解析:
I: This describes what /i(0wfa+zcfu,fo 5 qiz ,,bwp ky0r0pis happening in the diagram. When price decreases, quantity demanded increases as expressed by a movement along the demand curve.
II: This does not describe what is happening in the diagram, as an increase in demand refers to a shift of the demand cu0+50iu,zc k,0 yp(f qf/ifop brz, wwarve, not a movement along it.
III: The substitution effect is one of the reasons why the demand curve is downward-sloping.
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