As the above statement says two carbon atoms are bonded to each other with double bond, the suffix used for double bond is -ene& the prefix for two carbon atoms is eth- & it says four Hydrogen atoms are attached to carbons, 2 Hydrogens to each carbon above & below.
When we draw the structural formula it comes out that the molecule is ethene.
<em>Look at image for more </em><em>clarification</em>