单项选择题

Questions 1 to 5 are based on the following conversation.

A. After the first child, the spouse who makes less money will stop working to take care of the children.
B. The upper limit of household expense per week is $100, within which they might have own independent choice
C. For anything exceeding their own upper limit, they will not buy before reaching a common ground.
D. They can buy whatever they want so long it does not exceed $100 per week.