*Question*
You are presented with the question "If a person does what it may be due to a pathogen?" and the following answer choices: - is born - apoptosis - contracting - smoking - falls ill - symptoms - feels well - is happy Now knowing that bacteria can cause people to become ill and bacteria that cause disease are called pathogens, choose the best answer.
**Answer**
falls ill

*Question*
You are presented with the question "The first tetrapods were" and the following answer choices: - 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 Now knowing that amphibians are the first true tetrapods, or vertebrates with four limbs and all frogs are amphibians, choose the best answer.
**Answer**
in the frog family

*Question*
You are presented with the question "what is a major food source for humans?" and the following answer choices: - honeybees - poison - abalones - carbon monoxide - rabbit - trees - insects - stomach Now knowing that mollusks are a major food source for other organisms, including humans and an abalone is a shellfish or mollusk, choose the best answer.
**Answer**
abalones

*Question*
You are presented with the question "Forests naturally keep what?" and the following answer choices: - ants - fish - carbon - ferns - firs - rainfall - heat - protected Now knowing that carbon may be stored in sedimentary rock for millions of years and forests are a natural store of carbon, choose the best answer.
**Answer**
carbon