Final answer:
The main themes of the passage are the overconfidence people might have in technology and the importance of preparation to surpass historical achievements, which are represented by statements B and D respectively.
Step-by-step explanation:
Based on the context of the question, which is related to technological achievements and their impact on society and history, the two statements that best identify the main themes of the passage are:
- B. People can become overly confident in the capabilities of technology.
- D. Substantial preparation is necessary to exceed the prior feats of civilization.
These themes are evident as the passage discusses how technologies have evolved from early human societies to modern times, with specific reference to the cultural, physical, and economic impacts of these developments. For example, transatlantic voyages were made possible due to innovations in the fifteenth century, yet this did not solely make sea travel entirely safe. The history of technology shows that human confidence in technological progress can sometimes ignore the limitations and challenges inherent in pushing boundaries, hence statement B. Furthermore, the need for meticulous planning in order to achieve great feats, such as surpassing past accomplishments, is emphasized, thus reinforcing statement D.
The other statements either make absolute claims not supported by the passage (A and C) or seem irrelevant to the main themes identified (E and F).