The electronic configuration of Cu(II) is 3d9 whereas that of Cu(I) is 3d10, the correct statement about the aqueous solution of  Cu(II) and Cu(I) among the following is:

1. Cu(II) is more stable
2. Cu(II) is less stable
3. Cu(I) and Cu(II) are equally stable
4. Stability of Cu(I) and Cu(II) depends on the nature of copper salts