![](https://cos-cdn.shuashuati.com/pipixue-wap/2020-1230-1107-56/ti_inject-812ce.png)
The word that in paragraph 3, refers to
A.
the new freedom in design.
B.
the development of new and complicated products.
C.
making sure the different parts of a new product suit each other.
D.
the laborious working done on drawing and building a new products.