Which of the following situations is least likely to lead to high barriers to entry and monopoly supply（）

A. Natural resources are spread among many firms.

B. Governmental licensing and regulations are present.

C. Economies of scale are present.

国际化钻石模型将什么因素加入钻石模型中加以改进（）。

A.跨国公司商务活动

B.相关产业和支撑产业

C.结构和竞争者

D.机遇和政府