"Îi dau băiatului un ghiozdan roșu."

[Renardo11]

The multiple choice text offers the alternatives băiatului and băieților. In my opinion both make a correct sentence; I can give a single schoolbag to several boys. It would be better if the “wrong” alternative had a grammatical problem (such as a nominative noun).

[potestasity]

If the multiple choice still keeps the unstressed form of the pronoun (îi), then using the plural is indeed wrong. It should be "Le dau băieților un ghiozdan roșu."

[Renardo11]

Thanks / mulțumesc!