Answer:
Nuestros
Explanation:
It would be nuestros only if it includes more than one person and if the people involved are both Male and female. It would be nuestras is the people involved are only female. However, based on the fact that the sentence says tuyos, I believe they want you to use the word nuestros. However, if you accidentally left out any useful info, let me know and I'll help you. :)
