"Whose eggs are those?"
Translation:Čí jsou ta vajíčka?
The word order is hugely flexible, it allows the speaker to emphasise different words depending on a context, but of course, there are rules and it's not completely random, because then the whole sentence would be hard to understand. The pronoun "ta" is attached to the noun "vajíčka" and it agrees with the noun in gender/grammatical case/number. The fact that it agrees in these 3 categories means that it has to stand in front of that noun (not behind it). The noun might be described even more (eg. ta čtyři malá bílá vajíčka = those four small white eggs [nom.]; bez těch malých vajíček = without those small white eggs [genitive]; etc.), then all these develop the noun and agree in gender/case/number.
Another example: "malý kluk a vysoká holka" means that a boy is small and a girl is tall, but if you swapped the words and said "vysoký kluk a malá holka", it would be the exact opposite.
Čí jsou to vajíčka? (with several possible orders) is certainly also possible.
However, you have to distinguish
jsou to - those are
ta vajíčka - those eggs
That is syntactically different.
In English you could think of *"Whose are those eggs?" as a direct equivalent of "Čí jsou ta vajíčka?" but it is not actually natural in English.
I think I get it. Since 'to' was not in the choices, our correct choice was to use 'ta' with 'vajíčka', as an article, ta vajíčka, not as jsou ta on the end where ta would not be matching gender with vajíčka but standing alone as a noun. Those/the (article) eggs versus whose eggs are those (noun). Practice makes perfect.
I realize also I do not understand that it uses accusative here. Usually the accusative so far has been when talking about a 3rd party with he/she/they.