Solution

Homogeneous catalysis refers to catalytic reactions where the catalyst is in the same phase as the reactants. It applies to reactions in the gas phase and even in solids.

Haber's process: It combines nitrogen from the air with hydrogen derived mainly from natural gas (methane) into ammonia using a metal catalyst under high temperatures and pressures:
reaction is:
$$N_ 2(g) + 3 H_2(g) \overset { Fe(s) }{ \rightleftharpoons } 2NH_3(g)$$
reactants and catalyst are in a different phase (gas and solid, respectively)


Contact process: It involves the following steps:
1. makes sulphur dioxide by burning sulphur in excess of air/oxygen
2. converts the sulphur dioxide into sulphur trioxide in the presence of a catalyst vanadium pentoxide ($$V_2O_5$$)
3. converts the sulphur trioxide into concentrated sulphuric acid.
$$2SO_ 2(g) + O_2(g) \overset { V_2O_5(s) }{ \rightleftharpoons } 2SO_3(g)$$
reactants and catalyst are in a different phase (gas and solid, respectively)


Catalytic hydrogenation is the addition of hydrogen to an unsaturated compound with a double or triple bond such as oil. It reduces the compound and leaves fewer bonds between the carbons. The process of catalytic hydrogenation utilizes a metal catalyst such as nickel, palladium or platinum
$$C=C(l)+H_2(g)\overset { Ni(s) }{ \rightleftharpoons } CH-CH(l)$$
reactants and catalyst are in a different phase (liquid and solid, respectively)


Acid hydrolysis of methyl acetate is catalyzed by dilute acid, where it gets converted to methanol and acetic acid when heated under reflux with a dilute acid like dilute hydrochloric acid or dilute sulphuric acid.
$$CH_3COOCH_3(l)\overset { H_3O^+(l) }{ \rightleftharpoons } CH_3OH(l)+CH_3COOH(l)$$
reactants and catalyst are in the same phase (both liquid)

Therefore, option $$D$$ is correct.