Aqueous sodium hydroxide was added gradually, and then in excess, to the separate solutions of W, X, Y and Z. The outcomes are shown. Which row shows the metal ions present in the solutions?
- AW: aluminium, X: calcium, Y: copper(II), Z: iron(II)
- BW: aluminium, X: calcium, Y: iron(II), Z: copper(II)
- CW: aluminium, X: iron(II), Y: calcium, Z: copper(II)
- DW: calcium, X: aluminium, Y: copper(II), Z: iron(II)