Select the correct option: The professor's remarks were so dense with jargon that they bordered on .

Question

Select the correct option:

The professor's remarks were so dense with jargon that they bordered on .

1. A. opacity (Correct answer)
2. B. opaque
3. C. opacus
4. D. opalescent

Correct Answer

Option A — opacity

Detailed Solution & Explanation

The correct answer is opacity.

Key Points

• The phrase "bordered on ___" requires a noun, since *on* is a preposition and must take a noun as its object.
• Opacity is the noun — the quality of being impenetrable or difficult to understand, which fits remarks dense with jargon.
• Opaque is the adjective, opacus is Latin rather than English, and opalescent means showing shifting rainbow colours, which is unrelated.

Additional Information

• Deciding the required part of speech from the surrounding structure is the fastest route through fill-in-the-blank questions, often before considering meaning at all.
• The family here: opaque (adj.), opacity (n.), opaquely (adv.) — and note the spelling shift from *-que* to *-city*.
• Similar noun-forming patterns: *scarce → scarcity*, *tenacious → tenacity*, *audacious → audacity*, *veracious → veracity*.