Concept:Possessive pronouns show ownership without using an apostrophe.
Explanation:The sentence needs a possessive pronoun that means "belonging to us."
"Ours" is the correct possessive pronoun form.
Possessive pronouns like "ours", "yours", and "hers" never take an apostrophe.
Therefore, "our's" and "ours'" are incorrect.
"Our" is a possessive determiner, so it must be followed by a noun.
The best option is "ours".
Answer:A. ours