Passage Summary: Sharks have more cartilage and better cancer resistance than any other creature. Their cartilage contains a specific substance that stops tumors from growing, and human cancer patients have responded very well to treatments involving shark cartilage.

Reasoning: Sharks possess the highest cartilage-to-body mass ratio and the highest cancer resistance of any organism, likely due to a substance in their cartilage that prevents tumor growth by blocking new blood networks.

Analysis: In a 'Must be False' question, we are looking for a statement that directly contradicts the established facts in the stimulus. The passage sets several 'superlative' benchmarks, such as sharks having the highest ratio of cartilage and the greatest resistance to cancer. To find the correct answer, look for a claim that another organism has a higher cartilage ratio or that a different therapeutic measure produced a more positive response in terminal patients than shark cartilage did. Because this stimulus deals with biological and medical data, we must stick strictly to the provided percentages and comparisons without making outside assumptions.