The adsorption of hydrogen by metals is called –
Hydrogenation
Hydrogenation is a process of adding hydrogen to any compound and a metal is called as hydrogenation.In the options given dehydrogenation are reverse of hydrogenation.The phenomenon of attracting and retaining the molecules of a substance on the surface of a liquid or a solid resulting into a higher concentration of the molecules on the surface is called adsorption.The adsorption of gases on the surface of metals is called occlusion.