![](https://cos-cdn.shuashuati.com/pipixue-wap/2020-1230-1107-56/ti_inject-812ce.png)
Internal economies of scale
A.
may be associated with a perfectly competitive industry.
B.
cannot be associated with a perfectly competitive industry.
C.
are associated only with sophisticated products such as aircraft.
D.
cannot form the basis for international trade .