Fact 1: Smoking tobacco decreases stamina. Fact 2: Athletes use it to promote stamina and endurance. Given the two facts above, doing what with tobacco decreases athletic ability?

OPTIONS:
- steroids
- wearing
- A virus
- eating
- Heart rate
- smoking
- humans
- decorating

Answer: smoking

Problem: OPTIONS:
- keratin
- light
- heat
- fibers
- calcite
- mussels
- photons
- Neuron.
Q: Fact 1: When light enters the eye through the pupil , that light falls on the retina. Fact 2: Humans use both eyes to see a single image. Given the two facts above, what do humans use to see an image?
Answer: light

Problem:OPTIONS:
- Riding a bike
- environment
- reduced heat
- sleep
- competition
- evolution
- Summer
- Energy

Fact 1: Behaviors that improve fitness increase through natural selection. Fact 2: Natural selection is the mechanism of evolution. Given the two facts above, behaviors that improve fitness improve through what?
****
A: evolution

Fact 1: Fertilization occurs when sperm swim to an egg inside an archegonium. Fact 2: Sperm nuclei are released into the archegonium. Given the two facts above, what enters the egg?
OPTIONS:
- DNA
- flow of electrons
- insects
- Chemical energy
- fallopian tube
- sperm nuclei
- acid
- pollen
sperm nuclei

Fact 1: Mutation creates new genetic variation in a gene pool. Fact 2: Mutations Mutations are caused by random changes in genes. Given the two facts above, what creates new genetic variation in the gene pool?
OPTIONS:
- The bending of a ray of light
- passenger pigeons
- peachleaf willow
- Warm air moving into cold air
- random changes in genes
- that material's properties
- a tree falling
- By wind and rain

Answer: random changes in genes

input with options: Fact 1: Hair is a fiber that is found only in mammals. Fact 2: Bats have hair like all mammals so they can stay warm. Given the two facts above, what keeps mammals warm?
OPTIONS:
- fibers
- eyeballs
- white blood cells
- fur
- the skin
- sweating
- nostrils
- heat
output:
fibers