Q: Fact 1: Gills are used for breathing water by aquatic animals. Fact 2: Crustaceans are predominantly aquatic, breathing by means of gills. Given the two facts above, crustaceans breathe what through their gills? | OPTIONS:
- matter
- water
- saliva
- gametes
- semen
- liquid
- oxygen
- air
A: water

Q: Fact 1: Most mollusks have shells. Fact 2: Mollusks are invertebrates and are no exception. Given the two facts above, some invertebrates may have which feature? | OPTIONS:
- invertebrate
- fat
- gills
- exception
- three
- mollusk
- complex
- shell
A: shell

Q: Fact 1: Cross-pollination increases genetic diversity. Fact 2: Insects and hummingbirds are the primary pollinators. Given the two facts above, what animal increases plants genetic diversity? | OPTIONS:
- Reproduction
- Plant reproduction
- flowers
- Hummingbirds
- fish
- whales
- sharks
- animals
A: Hummingbirds

Q: Fact 1: Amphibians are the first true tetrapods, or vertebrates with four limbs. Fact 2: All frogs are amphibians. Given the two facts above, the first tetrapods were? | OPTIONS:
- major threat to health
- remains of prehistoric life
- in the frog family
- running and lifting
- competing for resources
- warm-blooded
- objects that have mass
- graptolites
A: in the frog family