Which compound can be heated under reflux with excess acidified potassium dichromate(VI) to form an organic product with the molecular formula C5H8O3\text{C}_5\text{H}_8\text{O}_3C5H8O3?
pentane-1,5-diol
3-hydroxypentanal
pentane-2,4-diol
2-methylbutane-1,2-diol
