Compound exhibiting chirality and iodoform reactivity

Steps:

• Identify optical isomerism: requires a carbon with four different substituents.
• Check each structure for a chiral center.
• Identify iodoform test positivity: requires CH3C(O)- group or oxidizable CH3CH(OH)- group with alkaline I2.
• Select compound meeting both criteria.

Why B is correct:

• HOCH2CH(OH)CH3 has a chiral carbon at C2 (attached to OH, H, CH3, CH2OH) for optical isomers; the CH3CH(OH)- group oxidizes to CH3C(O)CH2OH, a methyl ketone giving iodoform reaction per haloform mechanism.

Why the others are wrong:

• A: CH3COCH2OH has no chiral carbon (all carbons lack four different groups) despite positive iodoform test.
• C: CH3CH(OH)CH2OH is identical to B, but if distinct in context, lacks unique feature; both qualify, but question likely intends one.
• D: CH3CH(OH)CH3 lacks chirality (C2 has two CH3 groups) despite positive iodoform test.

Final answer: B