Crawfish disease presence is known to be non-existent.

• A. True
• B. False
• C. Not Sure
• D. Rare

Answer: (B)

This question tests how you handle absolute claims about disease status in crawfish populations. Saying that crawfish disease presence is known to be non-existent is an extreme statement. In biology and aquaculture, proving that a disease does not exist anywhere, at any time or in any stock, is practically impossible. Absence of evidence in some surveys or regions does not prove that disease can never occur. Diseases can be present in certain locations, under specific conditions, or in particular life stages, even if they’re not detected elsewhere.

So the claim is not supported by typical evidence, making it false. We would usually state that there is no current evidence of disease in the populations studied, or that disease presence has not been detected in those samples, rather than asserting that disease does not exist at all. The other options imply certainty, uncertainty, or rarity, but none accurately capture the idea that declaring universal non-existence is not justified.