将下面句子改写成两个短句（可调整语序、适当增加词语），做到既保留全部信息，又语言简明。

　　“红色旅游”是以革命纪念地、纪念物及其所承载的革命精神为吸引物，组织接待旅游者进行参观游览，实现学习革命历史知识、接受革命传统和振奋精神、放松身心、增加阅历的旅游活动。

答： ___     _                             

___     _                             

What is the point the speaker is trying to make about technology development

A．A mature technology requires less innovation.

B．Technical evolution is close to maturation in certain fields.

C．New types of energy are expected to mature in the near future.

D．Nanomaterials or photonics and carbon nanotubes are environmentally friendly.