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Extinction

Problem

The following graph shows the number of tetrapod (four-limbed animal) families on Earth over time, as indicated by the fossil record. The arrows indicate major mass extinction events.
The y axis of the line graph is labeled Number of tetrapod families and is marked at intervals of 50, 100, 150, 200, 250, 300 and 350. The x axis is labeled million years ago and is marked at intervals of 300, 250, 200, 150, 100, 50 and 0. The line begins at the intersection of the x and y axis and rises gradually. There are 3 arrows labeling different points on the line. The first arrow is at 250, 50 and is marked end-Permian extinction. The second arrow is at 200, 75 and is marked end-Triassic extinction. The third arrow is at 50, 150 and is marked end-Cretaceous extinction. After the third arrow there is a rapid vertical rise of the line, that continues until the end of the graph at 0, 350.
Which of the following statements is consistent with the information provided in the graph?
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