By What Means Do Humans Remove Nitrogen from the Soil

question 71

Multiple Choice

By what means do humans remove nitrogen from the soil? 

• A) harvesting nitrogen-poor crops 
• B) leaching water-soluble nitrate ions from soil through irrigation 
• C) applying organic fertilizers to agricultural land 
• D) mining nitrogen-poor mineral deposits

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Definitions:

Double-Blind Procedure

A research or testing methodology in which both the participants and the experimenters are unaware of who is receiving a specific treatment, to eliminate bias.

Experimental Research

A research method involving the manipulation of variables to determine cause-and-effect relationships.

Survey

A research method that involves collecting data from a sample of individuals through their responses to questions, aimed at gathering information about attitudes, behaviors, or characteristics.

Correlational Research

A type of non-experimental research method in which a researcher measures two variables, understands and assesses the statistical relationship between them without any causal assumption.