The answer you are looking for is A. If you need me to show you how I got the answer let me know. :)
One mole of hydrogen peroxide contains 6.02 x 10^23 molecules of hydrogen peroxide. And each molecule contains 4 atoms, so the answer is 4 x 6.02 x 10^23.
I believe the correct answer would be that electronegativity generally increases moving from left to right across a period. The periodic table of elements is arranged so that trends of the properties of the elements can be shown. For electronegativity, it decreases from right to left which means for the opposite direction it increases.
¿ cuál es la pregunta que intentas hacer?