Possessive or Plural

Which phrase can CORRECTLY replace the red words in the sentence below?
The movers packed the boxes of Mr. Blackstock. 

• Mr. Blackstocks boxes

• Mr. Blackstock's boxes

Our _________ new library is finished.

• towns

• town's

Is this word plural or possessive? The child's bike is being repaired today.

• plural

• possessive

Is this word plural or possessive or both? The puppies' toys were scattered on the floor.

• plural

• possessive

• both

The candy bar belongs to Sally.

• It is Sally's candy bar.

• The candy bar is Sallys. 

Shionnae has three _______

• pencils

• pencil's

My sister ate the ________ pizza.

• Polar Bears

• Polar Bear's

• Polar Bears'

The ___________ caves were dark, cold, and somewhat comfy.

• Polar Bears

• Polar Bear's

• Polar Bears'

The ___________ ate their lunch.

• Polar Bears

• Polar Bear's

• Polar Bears'

The _______________ mom protected it from the orca.

• Polar Bears

• Polar Bear's

• Polar Bears'