Identification of the organic compound
The given answer is wrong in many ways:

4 did not satisfy both criteria C and E, because it is not a chiral compound to begin with.
10 did not satisfy the criteria D, because it does give a precipitate with iodine in presence of $\ce{NaOH}$.

That gives only 5 in given answer to satisfy all criteria. Let's eliminate given compounds in systematic order:

That leaves only 5 and 6 to satisfy all criteria.