The flow of electrical current is possible because electrons are

Because the electrons are "free" (some of them, of course)

This means that they are not bounded to a particular molecule or particle, this means that they can "flow" along all the material, and the rules that they respect are the ones of electromagnetism (for example an electron can't flow freely, it must follow a "pattern" this is way wen you have electrical current all the electrons are flowing in the same direction)

Another answer can be: Because electrons are charged, of course, if the electrons weren't charged the electromagnetic fields would not affect them, and even if they flowed, there will not be ani electric charge.

So you need two things in order to have current, you need a charged object, and this object must be free so it can flow along with the material.

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.

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