单选题 Which statement can be the main idea of the passage?

A、 Glass is very useful because it has unusual qualities.
B、 Light signals have changed the use of glass in industry.
C、 Glass fibres have reduced the cost of telephone communication.
D、 The use of glass fibres to carry telephone messages in an interesting new development.

【正确答案】 D

【答案解析】[分析] 从文章第一段和最后一段可得D项。