单选题 What might be the most suitable title for the text?

A、 Two Important Tests on Airplanes.
B、 The Importance of Flying Safely.
C、 The Danger of Testing Airplanes.
D、 How Airplanes Are Made and Tested.

【正确答案】 A

【答案解析】[精解] 文章主题。文章第一句"Before a new type of airplane goes into service， every part of it is tested again and again．"明确给出了文章的主题：新款飞机投入使用前，其每个零件都要经过反复测试，与[A]选项一致，为正确答案。