The correct answer is (b.) conductor. A material that provides little or no resistance to the flow of electric current is called a conductor. A conductor is a known material that is used for a smooth flow of current with any barrier in one or more directions.
Action and reaction are equal in magnitude and opposite direction by they don't balance each other because they don't occur on the same body. Action is involved on one body and reaction is involved on another body.
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The correct answer would be D
Most objects move at a constant speed because of friction and acceleration. The constant speed keeps them in place, and keeps a balance.
