Consider the following reaction sequence

$\text{But - 2-ene}\stackrel{\text{ozonolysis}}{\to }X\underset{\text{(ii)}{\mathrm{H}}_3{0}^{+}}{\overset{\text{(i)}{\mathrm{CH}}_3\mathrm{MgBr}}{\to }}\mathrm{Y}\underset{573\mathrm{K}}{\overset{\mathrm{Cu}}{\to }}\mathrm{Z}$

The correct statements about Z are

I. It gives yellow precipitate with I₂ and NaOH solution
II. It undergoes disproportionation reaction in the presence of concentrated NaOH solution 
III. It undergoes wolff-Kishner reduction
IV. It forms red precipitate with Fehling's reagent