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 are also given a question about the story that requires an understanding of the relationship described in the background paragraph and the story. You need to come up with an answer to the given question; the answer will be a span from either the question or the story. In order to correctly answer the given question, you need to understand the relationship mentioned in the background paragraph and should be able to use it to understand that in the story. Your answer can not consist of any word that is not mentioned in any of these: the background paragraph, the story, or the question. You can directly copy and paste a span from the story or the question while answering the given question.

Background Paragraph: The particles of soup have greater average kinetic energy than the particles of water in the tub, explaining why the soup has a higher temperature. However, the mass of the water in the tub is much greater than the mass of the soup in the pot. This means that there are many more particles of water than soup. All those moving particles give the water in the tub greater total kinetic energy, even though their average kinetic energy is less. Therefore, the water in the tub has greater thermal energy than the soup. To compare the thermal energy of some other materials, go to the following URL and click on the interactive animation "Temperature and Thermal Energy.".
Story: Alexander is conducting reactions in his college chemistry class. In his first reaction, reaction A, he uses a large amount of reactants. In his second reaction, reaction B, he uses a much smaller amount of reactants compared to reaction A. As the reactions are proceeding, he measures that reactants in reaction A have low average kinetic energy. At the same time, reactants in reaction B have high average kinetic energy.
Question: Reactants in which reaction have smaller total thermal energy?
reaction B.

Background Paragraph: Allergy symptoms can range from mild to severe. Mild symptoms might include itchy eyes, sneezing, and a runny nose. Severe symptoms can cause difficulty breathing, which may be life threatening. Keep in mind that it is the immune system and not the allergen that causes the allergy symptoms. Allergy symptoms can be treated with medications such as antihistamines. Severe allergic reactions may require an injection of the hormone epinephrine. These treatments lessen or counter the immune system's response.
Story: Two groups of students went to the forest to explore nature and learn botany. Group D had some people experiencing mild allergy symptoms, and group C had a few folks with severe allergy symptoms, so they had to call the ambulance asap.
Question: Which group had fewer people that could be treated with antihistamines?
group C.

Background Paragraph: Clouds on Earth are made of water vapor. Venus's clouds are a lot less pleasant. They are made of carbon dioxide, sulfur dioxide and large amounts of corrosive sulfuric acid! The atmosphere of Venus is so thick that the pressure on the surface of Venus is very high. In fact, it is 90 times greater than the pressure at Earth's surface! The thick atmosphere causes a strong greenhouse effect. As a result, Venus is the hottest planet. Even though it is farther from the Sun, Venus is much hotter even than Mercury. Temperatures at the surface reach 465C (860F). That's hot enough to melt lead!.
Story: Two students studied the atmosphere of Earth and other planets from our solar system. Zack learned about Earth's atmosphere, while Ken learned about the atmospheric conditions on planet Venus.
Question: Which student learned less about carbon dioxide clouds?
Zack.