Dear Ecece,
I'm sorry that you also have got the answer wrong
"whose" is used for such POSSESSIVE ADJECTIVES as "my", "his" or "our". That is why "whose" must be followed by a Noun Phrase (NP), but this NP must NOT begin with ARTICLEs, such as "the" or "an" or DETERMINERs, such as "this" or "that".
1- The man [[[WHOSE
the wife was ill]]] was very unhappy. [INCORRECT]
2- The man [[[WHOSE wife was ill]]] was very unhappy. [CORRECT]
The Turkish equivalent : Karısı hasta olan adam mutsuzdu.
I hope these examples will give you an idea why WHOSE does not fit in the blank given in the question. If you are still having trouble understanding my explanation in English, I can readily do it in Turkish. Just take it easy.