The landscape of the Greater Yellowstone Ecosystem is the result of various geological processes over the last 150 million years. Here, Earth's crust has been compressed, pulled apart, glaciated, eroded, and subjected to volcanism. All of this geologic activity formed the mountains, canyons, and plateaus that define the natural wonder that is Yellowstone National Park.

Question

paragraph 2,While these mountains and canyons may appear to change very little during our lifetime, they are still highly dynamic and variable. Some of Earth's most active volcanic, hydrothermal (water + heat), and earthquake systems make this national park a priceless treasure. In fact, Yellowstone was established as the world's first national park primarily because of its extraordinary geysers, hot springs, mudpots and steam vents, as well as other wonders such as the Grand Canyon of the Yellowstone River.

(from "Yellowstone National Park: Geology" by National Park Service)

Question 1
This question has two parts. Answer Part A, and then answer Part B.

,begin emphasis,Part A,end emphasis,
What does the phrase ,begin emphasis,highly dynamic and variable,end emphasis, indicate about the mountains and canyons of Yellowstone in the first sentence of paragraph 2?

Question 1 Answer options with 4 options
1.	
They are extremely old features.

2.	
They are mainly why the park exists.

3.	
They are especially popular with visitors.

4.	
They are continually undergoing changes.

Question 2
,begin emphasis,Part B,end emphasis,
Which detail from the passage ,begin emphasis,best,end emphasis, supports the correct answer from Part A?

Question 2 Answer options with 4 options
1.	
"processes over the last 150 million years" (Paragraph 1)

2.	
"define the natural wonder" (Paragraph 1)

3.	
"active volcanic, hydrothermal (water + heat), and earthquake systems" (Paragraph 2)

4.	
"extraordinary geysers, hot springs, mudpots and steam vents" (Paragraph 2)

GPT-4o mini · Answer

**Question 1:** **Part A:** The phrase **"highly dynamic and variable"** indicates about the mountains and canyons of Yellowstone that: 4. They are continually undergoing changes. --- **Question 2:** **Part B:** The detail from the passage that best supports the correct answer from Part A is: 3. "active volcanic, hydrothermal (water + heat), and earthquake systems" (Paragraph 2)