Answer is: region A (from picture below).
Region A contains alkaline and earth alkaline elements (metals). This elements have lowest ionizations energy and easy remove valence electrons (alkaline metals one electron and earth alkaline metals two electrons). When element lose electrons, oxidation number of element grows (oxidation process).
<span>As the density of a substance increases the volume of a given
mass of the substance decreases</span>
The movement of gas through a tiny hole is called Effusion. Effusion occurs when there is a barrier with one or many small holes that prevent the gas to expand into the new volume unless a gas molecule happens to travel through the hole. The difference between Effusion and Diffusion is the barrier between the two volumes.
In a polyatomic ion, the ate ending indicates one more oxygen than the ite ending. D. more.