In aqueous solution Beryllium sulphate exist as:
A) [Be(H2O)4]SO4

B) [Be(H2O)6]SO4

C) [Be(H2O)3]SO4

D) [Be(H2O)5]SO4

In aqueous solution, beryllium sulfate (\(\text{BeSO}_4\)) primarily exists as a complex ion with water molecules. To determine the correct form, let’s consider the coordination chemistry of beryllium.

Beryllium (\(\text{Be}^{2+}\)) is a small ion with a high charge density, which means it has a strong tendency to form complexes with water. The coordination number of beryllium in aqueous solution is typically 4 because it prefers to form tetrahedral complexes due to its small size and high charge density.

The complex ion that forms with beryllium in water is \([Be(H_2O)_4]^{2+}\), not \([Be(H_2O)_6]^{2+}\) or any other coordination number. Therefore, the correct option is:

**A) \([Be(H_2O)_4]SO_4\)**