Which sentence correctly describes the cod stock situation in the Northwest Atlantic?

• A. The cod stocks were recovering due to improved quotas
• B. A disease in cod populations
• C. Over-fishing and climate changes caused a dramatic reduction in cod worldwide
• D. A market collapse led to fishing cessation

Answer: (C)

The main idea here is that human fishing pressure together with environmental changes can drive a fish stock to a sharp decline. For Northwest Atlantic cod, long-term overfishing reduced the number of breeding adults, making it harder for the population to replace itself. At the same time, climate-related changes in ocean conditions—like shifts in temperature, currents, and prey availability—alter cod habitat and survival, further reducing recruitment and growth of the stock. This combination explains a dramatic drop in cod stocks in that region.

The other scenarios don’t fit as well because a disease outbreak would need clear evidence of such an event driving the decline, which isn’t the primary driver identified for this case. A market collapse stopping fishing would reduce pressure but wouldn’t by itself explain why the stock fell in the first place. While quotas can influence recovery, they describe management after the decline rather than the cause of the stock collapse.