instruction:
Given a question and a context passage, generate the answer having the word or phrase from the context passage. Here, the answer should be a shortest continous span from the passage.
question:
Context: Rachel (Andrea Bowen), a high school girl, seems to have the life that most people envy: she has a steady boyfriend, some great friends, and a place on the school's soccer team. Preparing for college and separating from her boyfriend are the main worries of this teen, as she lives a carefree life like most girls her age. However, Rachel's world falls apart the day she discovers that Jason (Eric von Detton), a former sexual partner of hers that died an untimely death, was in fact HIV positive and an IV drug user. She immediately goes to an AIDS clinic to get a rapid test, which unfortunately comes back positive. Devastated by the fact that she may actually be infected with the virus, Rachel then confides in her substitute teacher, Sarah (Jennie Garth), who has secretly been living with the disease for years. But both young women are about to find out their secrets will not be kept secret for very long, as word begins to spread throughout their high school and rumors fly, making some of these students realize that they may not be as "clean" as they think they are. 
 Question: What were the results of Rachel's rapid test at the AIDS clinic?
answer:
positive


question:
Context: The apolipoprotein E type 4 allele is a susceptibility gene for late-onset Alzheimer's disease. Apolipoprotein E is found in neurons, some of which contain paired helical filaments made of the microtubule-associated protein tau. Previous studies have demonstrated that the apoE3 isoform, but not the apoE4 isoform, binds tau with high avidity. Because the microtubule-associated protein MAP2c also effects microtubule assembly and stability, we examined interactions between apoE isoforms and MAP2c. Similar to the tau-binding results, apoE3, but not apoE4, bound MAP2c. Binding was detectable down to 10(-9) M MAP2c and 10(-8) M apoE3. Isoform-specific interactions of apoE with the microtubule-associated proteins MAP2c and tau might affect intracellular maintenance of microtubules and could contribute to a time-dependent pathogenesis of Alzheimer's disease. 
 Question: Which ApoE isoform is associated with atherosclerosis and Alzheimer's disease?
answer:
apoe4 isoform


question:
Context: Ian Syster and his two-month-old son drowned in December 2004 in Keimoes following a car accident. 
 Question: What was the cause of death of Ian Syster?
answer:

accident