What is subsistence Agriculture.

 Subsistence farming is a form of production in which nearly all crops or livestock are raised to sustain the farm family, and rarely producing surpluses to sell for cash or store for later use.

Explanation: Mark me

Subsistence agriculture occurs when farmers grow food crops to meet the needs of themselves and their families on smallholdings. Subsistence agriculturalists target farm output for survival and for mostly local requirements, with little or no surplus.

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from the word list given, the most suitable words that relate to the reason information were written would be:  

objectivity: lack of bias, judgment, or prejudice

accuracy: free of mistakes, to be correct

authority: the ability to tell people what to do or believe in

content: to be satisfied  

it can be said that the author made the article to present objectivity, to provide accurate information, to be the authority in the subject that he or she writes, and to be satisfied of the information quality given out.