Some statements are given below about Ellingham diagram X=2Mg+O2→2MgOY=4/3Al+O2→2/3Al2O2Z=2C+O2→2COa) at 1120° C MgO will melt b) At the temperatures below  1400° C, Mg can reduce Al2O3 and at the temperature above  14000 C Al reduces MgOc)  At the temperature above 2000° C, carbon can reduce MgO The correct statement is /are

a) At 1120° C an abrupt increase in Δf0G value is observed. This is due to melting of MgO(s). b) Below 1400° C, “Mg – MgO” line is below “Al – Al2O3” line. ‘Mg’ can reduce Al2O3 below 1400° C.  Above 1400° C, “Al– Al2O3” line is below ‘Mg – MgO’ line. ‘Al’ can reduce MgO above 1400° C.C)Above metal  oxide is reduced by below element