Answer: A, burning fossil fuels
Gradual changes in the frequency of diseases over long periods are known as SECULAR TIME TRENDS. For example, the rate of mortality in USA due to coronary heart diseases over a period of time. Onset of puberty in girls is also a secular time trend.
Secular time trend is also referred as Secular Variation and Secular Drift.
Answer:
B. cougar
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Answer:
The answer is blue
Explanation:
The reason it is blue is because the blue color is the dominant gene, which means it is the gene that will express itself
