In a sentence from the passage, the word 'robust' describes a protocol. Which option best paraphrases 'robust'?

• A. Fragile
• B. Comprehensive and strong
• C. Outdated
• D. Questionable

Answer: (B)

When a protocol is described as robust, the idea is reliability and thorough effectiveness. In this context, robust implies that the protocol works well under different conditions and has solid, dependable performance. That’s why the paraphrase should convey both breadth and strength. “Comprehensive and strong” does this by signaling both wide coverage (comprehensive) and solid reliability (strong). The other options miss or contradict that sense: fragile suggests weakness, outdated implies it’s not current, and questionable hints doubt rather than assured effectiveness. So the best paraphrase is “Comprehensive and strong.”