The correct option is D 2C2H5OHH2SO4−−−−→C2H5−O−C2H5+H2O
If the catalyst is present in the same phase as the reactants, it is called homogeneous catalyst and this type of catalysts is called homogeneous catalysis. For example:
2C2H5OH(aq)H2SO4−−−−→C2H5−O−C2H5(aq)+H2O(l)
Here, both reactants and catalyst are present in the liquid phase.