Problem:OPTIONS:
- h2o
- tortoises
- viruses
- bacteria
- crocodiles
- octopus
- animals
- elephants

You are presented with the quiz "what has a nervous system?" But you don't know the answer, so you turn to your teacher to ask for hints. He says that "most invertebrates have a nervous system" and "an octopus is a very intelligent invertebrate". So, what's the best answer to the question?
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A: octopus

Problem:OPTIONS:
- h2o
- seeing light
- protect them
- Energy.
- resistance
- Energy
- courtship
- dogs

You are presented with the quiz "what can animal scent be used for?" But you don't know the answer, so you turn to your teacher to ask for hints. He says that "courtship is behavior that is intended to attract a mate" and "some animals attract mates with scent". So, what's the best answer to the question?
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A: courtship

Problem:OPTIONS:
- Sea species
- Coast guards
- animals
- Live Whales
- Shallow people
- fur seals
- a fish
- parasites

You are presented with the quiz "What live mainly in shallow coastal waters?" But you don't know the answer, so you turn to your teacher to ask for hints. He says that "marine species live mainly in shallow coastal waters" and "marine Science Marine science is the study of the sea". So, what's the best answer to the question?
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A: Sea species

Problem:OPTIONS:
- genetic diversity
- they body they live in
- earthquake history
- food and shelter
- gardening
- important habitats
- bird watching
- recreation

You are presented with the quiz "Estimating the age of trees can be used for what" But you don't know the answer, so you turn to your teacher to ask for hints. He says that "the number of rings in a tree trunk can be used to estimate the age of the tree" and "tree-ring dating the 1700 Cascadia earthquake". So, what's the best answer to the question?
****
A:
earthquake history