Biologists studied four reef sites and recorded coral cover (%) and two factors: water temperature anomaly (°C above normal) and fishing pressure (high/low). Site A, +0.5°C, low fishing, coral 70%; Site B, +0.5°C, high fishing, coral 35%; Site C, +2.0°C, low fishing, coral 50%; Site D, +2.0°C, high fishing, coral 18%. The researchers concluded that fishing pressure and temperature <em>both</em> harm coral, but fishing pressure has the larger effect at both temperature levels. The strongest data support for the "fishing has the larger effect" claim is ______
Which choice most logically completes the text using the data above?
- A
Site D's lowest coral cover of 18%.
- B
Site A's highest coral cover of 70%.
- Ccheck_circle
the +0.5°C pair (A 70% vs. B 35%, a 35-point fishing penalty) and the +2.0°C pair (C 50% vs. D 18%, a 32-point fishing penalty), each larger than the temperature penalty within fishing categories (A→C drops 20 points; B→D drops 17 points).
- D
the average coral cover across sites.
Explanation
To argue fishing has a larger effect than temperature, compare the within-temperature fishing drop with the within-fishing temperature drop. Choice B does both calculations and shows fishing's effect (<del>32-35 points) exceeds temperature's (</del>17-20 points) in every comparison. This is the only response that quantitatively supports the comparison.