The hubbard brook watershed deforestation experiment revealed that i) deforestation increased water runoff ii) nitrate concentration in waters draining the deforested area became dangerously high iii) calcium levels remained high in the soil of deforested areas

i believe the correct answer from the choices listed above is the first option. the scientists need to look at the   validity of data, claims, hypotheses, and observations before  developing an argument. they base their arguments on facts that are present and they make sure they have proofs. 

explanation:

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