Explanation

The sentence contrasts the economy’s current struggles with the secretary’s predictions for its long-term prospects. Since the secretary believes that technology
will lead to economic growth, the secretary’s outlook is an optimistic one. Thus the correct answer is “sanguine,” which can mean optimistic. Since there is no indication that the secretary’s view has wavered or is open to alternate interpretations, “irresolute,” “ambivalent,” and “equivocal” are all incorrect. The straightforward explanation of the rationale for the secretary’s outlook suggests that it is not an “arcane” one, making that choice incorrect as well. Thus the correct answer is sanguine (Choice B).
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