¿qué querías? yo querías un juguete. yo quería un juguete. yo queríamos un juguete. yo querió un juguete.

Yo quería un juguete.

Explanation:

The question is: What did you want?

And the options are tricky because in english we do not have conjugations per each person, meaning that it would be the same to say I wanted a bike, You wanted a bike, He wanted a bike, in spanish the conjugation of the verb changes with every person, so in spanish I wanted a toy, you would have to conjugate the verb want-quiero, for the first person in the past, Yo quiero- Yo quería. SO yo quería un juguete would be the answer.