You are given a background paragraph that describes one or more causal or qualitative relationships such as a relationship in economics or a scientific law and a story that makes use of the concepts or the relationship described in the provided paragraph. You need to come up with a question about the story that requires an understanding of the relationship described in the background paragraph. The generated question should not be answerable without both the background and story. Write a question about the story that requires a relationship in the background paragraph to answer. Check whether your question requires both the background paragraph and the story to answer. If your question can be answered by only one of these, try to rewrite your question so that it requires both. Note that "flipping" a word in the question can give rise to a new question where the answer will be different from the original question. Often, "flipping" a word gives rise to flipping the direction of the relationship, for example, from "increase" to "decrease."

[Q]: Background Paragraph: About 10% of sedimentary rocks are limestones. The solubility of limestone in water and weak acid solutions leads to karst landscapes, in which water erodes the limestone over thousands to millions of years. Most cave systems are through limestone bedrock.
Story: Peter visited two mountain ranges last summer. The Ozarks in Missouri, and the more massive and younger Colorado Rockies. He loved both ranges, but liked the caves systems and blue holes in the Ozarks a bit more.
[A]: Which mountains have a larger percent of limestone?

[Q]: Background Paragraph: Plants called epiphytes grow on other plants. They obtain moisture from the air and make food by photosynthesis. Most epiphytes are ferns or orchids that live in tropical or temperate rainforests (see Figure below ). Host trees provide support, allowing epiphyte plants to obtain air and sunlight high above the forest floor. Being elevated above the ground lets epiphytes get out of the shadows on the forest floor so they can get enough sunlight for photosynthesis. Being elevated may also reduce the risk of being eaten by herbivores and increase the chance of pollination by wind.
Story: Hawk and Brunt were two colleagues studying about plants. Later on, Hawk got specialized in normal plants, while Brunt decided to learn more about epiphytes.
[A]: Which colleague studied less about ferns?

[Q]: Background Paragraph: If a solution has a higher concentration of hydronium ions than pure water, it has a pH lower than 7. A solution with a pH lower than 7 is called an acid . As the hydronium ion concentration increases, the pH value decreases. Therefore, the more acidic a solution is, the lower its pH value is. Did you ever taste vinegar? Like other acids, it tastes sour. Stronger acids can be harmful to organisms. For example, stomach acid would eat through the stomach if it were not lined with a layer of mucus. Strong acids can also damage materials, even hard materials such as glass.
Story: Mike is studying chemistry for his exam. Today, he is studying the properties of acids. He picks up an acid solution that he labels as solution A. To compare it with another solution he chooses a solution that is not an acid. He labels it as solution B.
[A]:
If it is stronger, would solution A more likely or less likely be harmful to organisms than solution B?