In a recent experiment, scientists constructed an environment with

In a recent experiment, scientists constructed an environment with certain conditions that would contribute to excessive stress levels in lab rats. The rats were separated into two groups before being subjected to the stressful environment. One group was treated with linaloyl oxide through natural respiration while the other was not. Although it has been believed for centuries by certain medicinal researchers that the plant-based alcohol could be effective as an anxiety reducer, the broader medical community has remained skeptical. This skepticism will clearly change since the published results of the experiment reveal that there was an undeniable link between the administered substance and the moderate and controlled status of the treated rats' neutrophil granulocytes, a central component of the immune system indicative of stress, despite the manipulated, stress-inducing environment.

In the argument, the two portions in boldface play which of the following roles?


(A) The first is a theory that is in accordance with the argument's main position; the second is evidence that exposes the refutability of the defence of that position.

(B) The first is a speculative statement based on reasoning; the second is an elaboration of certain findings recorded as evidence that agrees with that speculation.

(C) The first is a questionable concept; the second develops that concept, forming a more comprehensive hypothesis.

(D) The first is an untested proposal of a causal relationship that the argument favors; the second calls that relationship into question.

(E) The first is historical evidence leading to the basis of the argument's position; the second is proof of that position