The correct option is D all of the above
All ketones and aldehydes that has CH3CO group will answer haloform test.
(a) 2-Pentanone
(CH3CH2CH2O||CCH3)
(b)
Ethanol under the reaction condition is oxidised to acetaldehyde (CH3CHO )and hence it shows haloform test.
(c) 2-hexanone
(CH3CH2CH2CH2O||CCH3).
As all the above structures contain CH3CO group, they will give positive haloform test.