Which sentence uses possessive pronouns correctly? A. The responsibility for the fallen tree is their's. B. That pumpkin looks like ours. C. I think that big red suitcase is her's. D. My dog lost it's collar somewhere in the park.

D. My dog lost its collar somewhere in the park. I don't know if you typed this question but if you didn't you should talk to your teacher. Hers doesn't have an apostrophe. Their's doesn't have an apostrophe. It's doesn't have an apostrophe. Possessive pronouns like these don't require pronouns, only when you are using a persons name, for instance; Bravemoon's or Abbie's  Hope this helped!~

D. My dog lost its collar somewhere in the park