(Q012) The Paleozoic Era ended with a mass extinction event that was likely caused byGroup of answer choicesthe formation of Pangaea.intense volcanic activity.the formation of high-latitude ice sheets.the evolution of land plants.

The Paleozoic Era ended with a mass extinction event that was likely caused by intense volcanic activity. This is known as the Permian-Triassic Extinction Event or the "Great Dying," which occurred around 252 million years ago. It's considered the most severe extinction event in Earth's history, with up to 96% of all marine species and 70% of terrestrial vertebrate species becoming extinct.

Here's a step-by-step explanation:

1. The Paleozoic Era is a significant period in Earth's history that lasted from about 541 to 252 million years ago. It ended with a mass extinction event, which is a sudden, sharp decrease in the number of species in a relatively short period of time.

2. The cause of this mass extinction event is believed to be intense volcanic activity. This is based on evidence of massive volcanic eruptions in what is now Siberia, which would have released large amounts of greenhouse gases into the atmosphere.

3. These gases could have caused a rapid increase in global temperatures, a process known as global warming. This would have led to a variety of environmental changes, including ocean acidification and a decrease in oxygen levels in the water, which would have been devastating for marine life.

4. While the formation of Pangaea, the evolution of land plants, and the formation of high-latitude ice sheets all occurred during the Paleozoic Era, they are not believed to be the primary causes of the mass extinction event that ended this era.