Question: Fact 1: Food consists of organic molecules that store energy in their chemical bonds.  Fact 2: Food is the ideal source of nutrients.  Given the two facts above, what consists of organic molecules that store energy in their chemical bonds?
Answer: source of nutrients

Question: Fact 1: Mating is generally preceded by courtship.  Fact 2: Courtship is similar across species.  Given the two facts above, what is generally similar across species?
Answer: mating

Question: Fact 1: Carbon dioxide concentrations in the air have increased over the last decade dramatically.  Fact 2: Carbon dioxide, CO2, is usually a harmless gas.  Given the two facts above, what concentration in the air has increased dramatically over the last decade?
Answer:
CO2