"यह किसका खाना है?"

Translation: Whose food is this?

[chris.beaton3]

"Whose is this food" should be accepted surely?

[Wilbur111]

No. That would be "yehe kana kiska he?"

In the Duo sentence they're asking "this is whose food?" Not "whose is this food?"

They're asking about "this" not "this food".

[VijayGanes911384]

It should be "Who's food is this" right?

[Ashmath.]

Vijay,

If you separate the contraction who's into 'who is', the sentence, " Who is food is this?" does not make sense.

I would say a good number of English speakers, native speakers, School educated /otherwise may think that that is how the word 'whose' is spelled in the sentence, but whose is the appropriate possessive pronoun, same category as his, mine, hers, ours

Whose is this? It's ours. No, it's hers.

[Little_Lalou]

Could you say Kiska yaha khana hai?

[DavidSpect5]

"This is whose food?" was not accepted.