Question: Fact 1: Antigens are molecules that the immune system recognizes as foreign to the body. Fact 2: An allergy is a reaction to a substance the body recognizes as foreign. Given the two facts above, an allergy can be caused by?
OPTIONS:
- antigens
- Pesticides
- cold weather
- fever
- viruses
- food
- Smoking
- germs
Answer: antigens

Question: Fact 1: Plucking a string can cause that string to vibrate. Fact 2: All guitars produce sound through the mechanical vibration of strings. Given the two facts above, how does a guitar create sound?
OPTIONS:
- electrically
- mechanical
- Amplifying it with electricity
- The musician being trained
- Tuning it properly
- Plucking a string
- Through play
- lowered energy cost
Answer: Plucking a string

Question: Fact 1: Most amphibians breathe with gills as larvae and with lungs as adults. Fact 2: All frogs are amphibians. Given the two facts above, what can breathe with gills as larvae and with lungs as adults?
OPTIONS:
- humans
- viruses
- a fish
- animals
- bats
- frogs
- bacteria
- air
Answer:
frogs