Correct Answer: B
Explanation:
The key phrases that indicate how the blank for this question should be completed are: “circumspect,” “reluctant,” and “but once.” Taken together they point to completing the blank with something that is opposite in some way to the two cited adjectives. Among the answer choices, “intransigent” and “resolute,” although not strictly synonymous, both fit the logic of the description given here for completing the blank and create sentences that are similar in meaning. “Lax” and “negligent” are clearly similar in meaning and would create sentences similar in meaning, but they continue the sentiment voiced in the initial clause rather than contrasting with it. “Deferential” and “obsequious” are also similar in meaning, but their emphasis on “politeness,” while not strictly synonymous with reluctance and circumspection, like “lax” and “negligent” fail to pick up on the expected contrast.