Acidity of acidic compounds depend on the stability of their conjugate bases. The correct order of acidity of the underlined H in the following compounds, assuming that all the compounds exist in the keto form, is

A

(ii) > (iii) > (iv) > (i)

B

(iv) > (iii) > (i) > (ii)

C

(iii) > (ii) > (iv) > (i)

D

(i) > (iii) > (iv) > (ii)