单选题 22. The hulls of the deep-sea submersibles of the future will be constructed from glass, not from special steel or aluminum alloys. The reason is that metals have a grainy microscopic structure, which makes metal hulls susceptible to cracking between the grains under deep- sea pressures. Glass hulls are immune to this problem because glass, though a solid in appearance, can be considered a fluid because it flows when under pressure.
Which of the following can be most reliably inferred from the passage above? ______

A、 Fluids lack grainy microscopic structure.
B、 All so-called solids are merely extremely slow-running fluids.
C、 The only glass that ever cracks is microscopically grainy.
D、 Glass is superior to steel and aluminum as a construction material.
E、 Glass hulls have consistently outperformed metal hulls in recent deep-sea operations.

【正确答案】 A

【答案解析】 A：该选项和原文结论保持一致，正确。
B：本文只是说玻璃这种固体其实是流体，不意味着所有固体都是流体，不选。
C：本文没有提到玻璃开裂过。
D：本文的讨论范围仅限于潜水器，与建材无关，不选。
E：文章没提最近的深海航行，不选。