<h3><u>Answer;</u></h3>
A. global temperatures drop several degrees after several massive volcanic eruptions
<h3><u>Explanation;</u></h3>
- <em><u>A mass extinction refers to a widespread and a rapid decrease in the Earth's biodiversity. </u></em>
- <em><u>Mass extinctions may occur due to a number of reasons which includes, asteroid impacts, climate change, massive volcanic eruptions or a combination of all these causes. </u></em>
- <em><u>An example of mass extinction was during the Mesozoic Era, that led to the extinction of dinosaurs, about 65 million years ago.</u></em>
The last common ancestor of gymnosperms and angiosperms possessed the same characters such as pollen, seeds, and vascular tissue.
<h3>What are angiosperms and gymnosperms?</h3>
The gymnosperms are a group of plant that are known as seed- producing plants such as Ginkgo, gnetophytes, cycads etc.
Angiosperms are the plant that produces flowers and having seeds enclosed within their fruit.
Gymnosperms have no production of flowers and fruits and they contain seeds without cover on the surface of their leaves.
Therefore,last common ancestor of gymnosperms and angiosperms possessed the same characters such as pollen, seeds, and vascular tissue.
Learn more about angiosperm and gymnosperm here:
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