<h3>Answer:</h3><h3>D</h3><h3 /><h3>Step-by-step explanation:</h3><h3></h3><h3>In a function, an input (x) value should have only one output (y) value.</h3><h3 />
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<em>Example: (View attached image below). </em><em>Table A</em><em> is a function because each </em><em>x </em><em>value has only 1 </em><em>y</em><em> value. But </em><em>Table B</em><em> is not a function because the </em><em>x value</em><em> of </em><em>4 </em><em>has </em><em>2 y values</em><em>.</em>