- 搜标题
- 搜题干
- 搜选项
单项选择题
The opportunity cost of taking this exam is equal to ( )
A．the value of the time that you spend taking the exam.
B．the expense of your textbook.
C．the tuition payment for this class.
D．the number of questions.
B．the expense of your textbook.
C．the tuition payment for this class.
D．the number of questions.
