input with options: Fact 1: Plucking a string can cause that string to vibrate. Fact 2: Nylon string is by far the softest sound on the guitar. Given the two facts above, what do guitars make sound with?
OPTIONS:
- friction
- vibration
- voltage
- energy
- power
- bamboo
- mechanical
- heat energy
output: vibration

input with options: Fact 1: When the body is hot , sweat is produced to cool the body. Fact 2: Exercise, fever, and heat cause the body's temperature to rise. Given the two facts above, what causes sweat to be produced to cool a person down?
OPTIONS:
- exercise and fever
- wool pants
- the sun
- Movement of an air mass
- shooting stars
- Evaporation
- centralized nervous system
- water vapor
output: exercise and fever

input with options: Fact 1: If a thermal conductor is exposed to a source of heat then that conductor may become hot. Fact 2: Copper is a great thermal conductor. Given the two facts above, what can easily become hot if exposed to heat?
OPTIONS:
- an object
- engines
- vehicles
- animals
- the skin
- clams
- copper
- Mammal
output: copper

input with options: Fact 1: Using renewable resources to generate power reduces greenhouse gases. Fact 2: Carbon dioxide is a greenhouse gas. Given the two facts above, what does using renewable resources to generate power reduce?
OPTIONS:
- lowered energy cost
- solar power
- climate
- evergreen trees
- Heat energy
- oxygen
- carbon dioxide
- kinetic energy
output:
carbon dioxide