To determine the correctness of these statements and choose the correct option, we need to understand the concepts of homoleptic and heteroleptic complexes:

Homoleptic Complex: A complex in which a central atom is surrounded by only one kind of donor atom or identical ligands is known as a homoleptic complex. An example would be $$[\mathrm{Co}(\mathrm{NH}_3)_6]^{3+}$$, where all the ligands are ammonia ($\mathrm{NH}_3$).

Heteroleptic Complex: A complex in which a central atom is surrounded by more than one kind of donor atom or different ligands is known as a heteroleptic complex, such as $$[\mathrm{Co}(\mathrm{NH}_3)_4\mathrm{Cl}_2]^{+}$$ which contains two different types of ligands, ammonia ($\mathrm{NH}_3$) and chloride ($\mathrm{Cl}^-$).

Statement I: $$[\mathrm{Co}(\mathrm{NH}_3)_6]^{3+}$$ is a homoleptic complex whereas $$[\mathrm{Co}(\mathrm{NH}_3)_4\mathrm{Cl}_2]^{+}$$ is a heteroleptic complex.

This statement is accurate because $$[\mathrm{Co}(\mathrm{NH}_3)_6]^{3+}$$ indeed is a homoleptic complex as it consists only of ammonia ligands. Conversely, $$[\mathrm{Co}(\mathrm{NH}_3)_4\mathrm{Cl}_2]^{+}$$ is a heteroleptic complex, containing both ammonia and chloride ligands.

Statement II: Complex $$[\mathrm{Co}(\mathrm{NH}_3)_6]^{3+}$$ has only one kind of ligands but $$[\mathrm{Co}(\mathrm{NH}_3)_4\mathrm{Cl}_2]^{+}$$ has more than one kind of ligands.

This statement is also true. As explained, in $$[\mathrm{Co}(\mathrm{NH}_3)_6]^{3+}$$, there is only one type of ligand (ammonia), and in $$[\mathrm{Co}(\mathrm{NH}_3)_4\mathrm{Cl}_2]^{+}$$, there are two different types of ligands (ammonia and chloride), which is consistent with the definition provided.

Conclusion: Both Statement I and Statement II are true. Therefore, the correct choice is:

Option A: Both Statement I and Statement II are true