Major extinctions of dinosaurs are associated with large meteor impacts, including the final extinction that wiped them out at the Cretaceous-Tertiary boundary. The particulate matter that would have arisen as a result of impact would have entered the atmosphere and had secondary impacts. Some scientists believe that a fundamental difference between mammals and dinosaurs allowed mammals to survive this event, but doomed the dinosaurs. What may have characterized the last generation of dinosaurs as they went extinct?
A. Highly skewed sex ratios
B. Hormonal disruptions due to contaminated water
C. Inability to recognize mates due to diminished sunlight
D. Lungs clogged with dust
E. Weak eggshells due to radiation
Answer: A
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