An aluminium strip is kept immersed in freshly prepared ferrous sulphate solution taken in a test tube, the change observed is that

Question

$\begin{array}{1 1} \text{(a) Green solution slowly turns brown} \\ \text{ (b) Lower end of test tube become slightly warm} \\ \text{ (c) A colourless gas with the smell of burning sulphur is observed} \\ \text{ (d) Light green solution changes to blue.} \end{array}$