Q: Given the background: Predators play an important role in an ecosystem. For example, if they did not exist, then a single species could become dominant over others. Grazers on a grassland keep grass from growing out of control. Predators can be keystone species . These are species that can have a large effect on the balance of organisms in an ecosystem. For example, if all of the wolves are removed from a population, then the population of deer or rabbits may increase. If there are too many deer, then they may decrease the amount of plants or grasses in the ecosystem. Decreased levels of producers may then have a detrimental effect on the whole ecosystem. In this example, the wolves would be a keystone species. and the situation: Mike is studying the predator prey relationship. He is specifically studying three species, species A, species B, and species C. Species A is a predator; species B is the prey; and species C is a plant species that species B lives on. Mike now needs to figure out how the predator prey relationship balance the ecosystem. Answer the following question: If species A population decrease, would it affect the ecosystem positively or negatively?
A: negatively

Q: Given the background: Using longitudinal data from over 100 countries, Diener and his colleagues showed that rich countries are in general happier than poor countries (Diener, Tay, & Oishi, 2013).[17] Also, life satisfaction for most countries goes up as they become wealthier over time. Diener identified three factors that influence the relationship between income and SWB. Namely, rising income most likely results in higher SWB when it leads to greater optimism, financial satisfaction and household material prosperity among citizens. Furthermore, Diener and his colleagues investigated the relationship between income and different elements of SWB. They illustrated that income has stronger influence on people's evaluation of their lives than the positive or negative emotions they experience over time (Diener, Kahneman, Tov, & Arora, 2010).[18] The study points to the necessity to evaluate different elements of SWB separately instead of treating happiness as a single entity. and the situation: Over the years, the town of Euphoria has grown more successful and wealthier than anyone ever thought. As the wealth has increased and people have acquired more material possessions, their outlook on life has become more positive and it has been noted that the citizens have a lower incidence of depression. The town of Zenphora, on the other hand, has taken a downward financial turn over the past 50 years. The citizens have had to sell their worldly goods just to make ends meet and many do not have a good feeling about what their future holds. Answer the following question: Due to financial success, has the SWB in Euphoria increased or decreased?
A: increased

Q: Given the background: Hemophilia is the name of a group of hereditary diseases that affect the body's ability to control blood clotting. Hemophilia is caused by a lack of clotting factors in the blood. Clotting factors are normally released by platelets. Since people with hemophilia cannot produce clots, any cut can put a person at risk of bleeding to death. The risk of internal bleeding is also increased in hemophilia, especially into muscles and joints. This disease affected the royal families of Europe. and the situation: Two twin sisters were taken to the doctor's office by their parents. It turned out that Mary had hemophilia while Ann didn't have any blood disease. Answer the following question: Which sister was more exposed to the risk of bleeding to death?
A: Mary

Q: Given the background: Hepatitis viruses can develop into a chronic viral infection that leads to liver cancer. Infection by human T-lymphotropic virus can lead to tropical spastic paraparesis and adult T-cell leukaemia. Human papillomaviruses are an established cause of cancers of cervix, skin, anus, and penis. Within the Herpesviridae, Kaposi's sarcoma-associated herpesvirus causes Kaposi's sarcoma and body-cavity lymphoma, and EpsteinBarr virus causes Burkitt's lymphoma, Hodgkin's lymphoma, B lymphoproliferative disorder, and nasopharyngeal carcinoma. Merkel cell polyomavirus closely related to SV40 and mouse polyomaviruses that have been used as animal models for cancer viruses for over 50 years. and the situation: Two cousins both have chronic viral infections. Tim has Kaposi's sarcoma-associated herpesvirus, while Nate has the EpsteinBarr virus. Answer the following question: Which cousin has a lower chance of developing B lymphoproliferative disorder?
A:
Tim