Examkin

Question

Difficulty: HardPart-to-Whole Rhetorical Function

Astronomers analyzing data from space probes have identified organic macromolecules in the plumes of water vapor erupting from Saturn’s moon Enceladus. Some researchers argue that the presence of these compounds indicates that the moon's subsurface ocean could harbor prebiotic chemical pathways. Other scientists caution that these organic molecules could be produced by abiotic geochemical processes, such as serpentinization, which do not involve biological activity. Consequently, establishing whether Enceladus possesses the conditions necessary for life requires more detailed isotopic analysis of the plume constituents rather than simple molecular identification.

Which choice best describes the function of the underlined sentence in the text as a whole?

  1. A
    It summarizes the primary conclusion of the text regarding the viability of prebiotic chemistry on Enceladus.
  2. It presents an alternative explanation for a phenomenon to qualify a hypothesis introduced in the preceding sentence.Answer
  3. C
    It provides definitive evidence that abiotic reactions are more common than biotic processes in planetary systems.
  4. D
    It identifies serpentinization as the only known source of water vapor plumes on Saturn's moons.

Answer

The choice that states the underlined sentence presents an alternative explanation for a phenomenon to qualify a hypothesis introduced in the preceding sentence.
The correct answer accurately describes the rhetorical function of the underlined sentence. The preceding sentence introduces the hypothesis that organic compounds in Enceladus's plumes suggest prebiotic chemistry in its subsurface ocean. The underlined sentence introduces an alternative explanation—that these compounds could be produced by abiotic geochemical processes like serpentinization—thereby qualifying the optimistic interpretation of the discovery.

Step-by-Step Solution

1
Read the entire passage to understand its overall structure and main argument.
The passage discusses the discovery of organic macromolecules in Enceladus's plumes, a hypothesis that this suggests prebiotic chemistry, an alternative abiotic explanation, and a conclusion that isotopic analysis is needed.
To establish a baseline understanding of the passage structure before focusing on the specific sentence.
2
Examine the underlined sentence in relation to the sentences immediately preceding and following it.
The preceding sentence proposes that organic molecules indicate prebiotic pathways. The underlined sentence introduces an alternative explanation (abiotic processes) that counteracts or qualifies this idea.
To determine how this specific part functions within the logical progression of the text.
3
Evaluate the answer choices to find the one that accurately describes this relationship while rejecting choices that mischaracterize the text or generalize inappropriately.
The option describing the sentence as qualifying a hypothesis with an alternative explanation is correct.
To choose the best match for the rhetorical function.

Key Concept

Part-to-Whole Rhetorical Function
Estimated Time:2m 0s
Rate this question

Topics

Part-to-Whole Rhetorical Function

More questions from this topic