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: Continued heating of the water after the ice has completely melted will now increase the kinetic energy of the liquid molecules and the temperature will rise. Assuming that the atmospheric pressure is standard, the temperature will rise steadily until it reaches 100°C. At this point, the added energy from the heat will cause the liquid to begin to vaporize. As with the previous state change, the temperature will remain at 100°C while the water molecules are going from the liquid to the gas or vapor state. Once all the liquid has completely boiled away, continued heating of the steam (remember the container is closed) will increase its temperature above 100°C. 
Story: Tommy sets two pots of water, Pot A and Pot B, on the stove and sets each burner to a different temperature. Tommy is unable to see what the temperatures of the burners are though. He sits around patiently and waits until he notices that Pot B's water is beginning to vaporize, while Pot A's water is not vaporizing. 
Question: The water in which pot is hotter?
Pot B.

Background Paragraph: For example, a radioactive isotope of iodine (I-131) is used in both the diagnosis and treatment of thyroid cancer. The thyroid will normally absorb some iodine to produce iodine-containing thyroid hormones. An overactive thyroid gland will absorb a larger amount of the radioactive material. If this is the case, more and more radioactive iodine can be administered, where it will cluster in the diseased portion of the thyroid tissue and kill some of the nearby cells. Cancer treatments often cause patients to feel very sick, because while the radiation treatment kills the unwanted cancer cells, it causes damage to some healthy cells in the process. 
Story: John is a doctor in a local hospital. Today, he is seeing two patients, patient A and patient B. Patient A has thyroid cancer, but patient B does not have thyroid cancer. John is trying to see the difference between these two patients' reports. 
Question: Which patient would risk damaging healthy cells, patient A or patient B?
patient A.

Background Paragraph: Greenhouse Effect: The solar energy reaching the surface of the Earth is concentrated in short wavelengths, which can easily penetrate the greenhouse gases, such as carbon dioxide and methane. The Earth, however, is cooler than the sun and it radiates its heat in the form of energy in the far infrared range. These longer wavelengths are partially absorbed by the greenhouse gases and some of the solar heat is returned to Earth. At a certain temperature these processes are in equilibrium and the surface temperature of the Earth is stable. However, if more greenhouse gases are put in the atmosphere the amount of trapped terrestrial radiation increases, leading to an increase in global temperature. 
Story: David was visiting the natural history museum. He noticed two charts that showed the climatic conditions of the earth in two time periods, time A and time B. Time A showed earth's overall climate in the sixteenth century when there were less greenhouse gases in the atmosphere. And time B showed earth's overall climate in the present century with more greenhouse gases in the atmosphere. David found some interesting differences between these two charts. 
Question: Which period would see more trapped terrestrial radiation, time A or time B?

time B.