Amongst the following statements regarding adsorption, those that are valid are

(a) $$\Delta $$H becomes less negative as adsorption proceeds
(b) On a given adsorbent, ammonia is adsorbed more than nitrogen gas
(c) On adsorption, the residual force acting along the surface of the adsorbent increases
(d) With increase in temperature, the equilibrium concentration of adsorbate increases

An organic compound ‘A’ (C₉H₁₀O) when treated with conc. HI undergoes cleavage to yield compounds ‘B’ and ‘C’. ‘B’ gives yellow precipitate with AgNO₃ where as ‘C’ tautomerizes to ‘D’. ‘D’ gives positive iodoform test. ‘A’ could be

The shape / structure of [XeF₅]^– and XeO₃F₂, respectively, are

The major product of the following reaction is :