[求助]一道逻辑题的解答

The sense of delayed gratification, of working now for later pleasure, that has shaped the economic behavior of our society. However, that sense is no longer nurtured as consistently in our children as it was once was. For example, it used to take a bit of patience to put together the toys that children got in cereal boxes; now the toys come from the boxes whole.

which of the following is an assumption of the page above:

A. The toys in cereal boxes have changed partly because the economic conditions of our society have improved.

B. Thr influence of promotion gimmicks on the economic behavior of our society has increased over the years.

C.The toys that used to come in cereal boxes were put together by the same children who played with them.

D.Part of the pleasure of any toy lies in putting the toy together before playing with it.

E.Today's children do not expect a single toy to provide pleasure for a long period of time,

怎么都想不通答案为什么选C，我选的是D，期待各位好心人的解答，本人才接触逻辑，实在还有太多不懂的地方，如有何白痴的地方，还请见谅。

不选D是因为题干其实不是讨论pleasure的问题，而是讨论培养孩子的今昔差别问题。

选C是说明，必须有这样一个前提，那就是以前培养孩子这种耐性的可能是由于put together这个toy都是一个孩子完成的，才有了这个patience的培养过程，要是不是一个孩子完成的，就不存在培养其耐性的过程了，也就不存在和今昔的对比。那作者的结论that sense is no longer nurtured as consistently in our children as it was once was又从何说起呢？

我是这样理解的，不知道是否是大多数人的理解，欢迎交流！

哦，茅塞顿开~~

我一直理解成了后来新出的玩具是那个玩的小孩组装的,所以就一直想不明白.这个怎么会成为assumption?