Number 9 according to the article which is an effect of volcanic eruptions

In the following conversation, which group discussion technique does emily most clearly show?

The cheerleading squad practiced their routine, they were still not ready to perform for an audience. choose the best transitional word or phrase to complete the sentence. a) however b) besides c) although d) therefore

What is the main idea of this paragraph from the volcanoes section of the ready. gov website