单选题 Which of the following statements concerning nanotechnology research is most directly suggested in the passage?

• (A) Nanotechnology research tends to be more focused on the process of building multiple molecules than chemistry research.
• (B) Nanotechnology research is increasingly less bound to operations on the microscopic level than it once was.
• (C) The practitioners of nanotechnology tend to be more optimistic than pragmatic in choosing its methodology.
• (D) Nanotechnology research involves a much greater level of technical knowledge, on the whole, than chemistry research.
• (E) Nanotechnology research tends to be more concerned at this stage with precision than convenient mass production.